[Timing of gonadectomy in patients with complete androgen insensitivity syndrome]. / Quand proposer une gonadectomie chez les patientes présentant une insensibilité complète aux androgènes ?

Complete androgen insensitivity syndrome is the most frequent cause of disorder of sexual development in 46 XY patients. It is caused by mutations of the AR gene coding for the androgen receptor. Transmission is X-linked and mutations are most of the time inherited. It leads to a complete lack of response to androgen resulting in the presence of female external genitalia in 46 XY patients, normal but undescended testes and lack of female internal genitalia due to the secretion of anti-Müllerian hormone by male gonads. Traditionally, gonadectomy was proposed before puberty to decrease the risk of gonadal malignancy. However, more recent studies underlined the benefits of postponing gonadectomy until after pubertal development. Benefits of deferred gonadectomy are spontaneous pubertal development through peripheral aromatization of testosterone into oestrogens and the chance for the patient to have an active role in the decision-making process. After gonadectomy, hormone replacement therapy is required in order to prevent complications due to hypogonadism such as osteoporosis, cardiovascular diseases and a reduction of life expectancy.

L'insensibilité aux androgènes est l'étiologie principale des troubles du développement sexuel chez des patientes 46 XY. Elle est due à des mutations du gène AR qui code pour le récepteur des androgènes. Le mode de transmission est lié à l'X et les mutations sont le plus souvent héritées. Il en résulte une absence d'action des androgènes sur leurs récepteurs entraînant la présence d'organes génitaux externes féminins chez des patientes 46 XY, de testicules normalement développés en position abdominale ou inguinale et en l'absence d'organes génitaux internes féminins due à la sécrétion d'hormone anti-müllérienne par les gonades masculines. La gonadectomie était auparavant effectuée en période pré-pubertaire en raison du risque suspecté de développement de néoplasie maligne. Des données récentes suggèrent la possibilité de postposer cette intervention après le développement pubertaire. Le risque de transformation maligne pré-pubertaire des gonades est faible, et différer la gonadectomie permet un développement pubertaire naturel grâce à l'aromatisation périphérique de la testostérone en œstradiol. Ce délai permet d'impliquer activement la patiente dans la prise en charge de sa pathologie. Après la gonadectomie, un traitement hormonal substitutif par œstrogènes est indiqué pour prévenir les complications dues à l'hypogonadisme telles que l'ostéoporose, les maladies cardio-vasculaires et la réduction de l'espérance de vie.

[Technological progress and novelty in insulin therapy during those last ten years for diabetes children and adolescents]. / Progrès technologiques et nouveautés en insulinothérapie au cours de la dernière décennie chez l'enfant et l'adolescent diabétiques.

These last few years, new advances in technologies and modern insulin regimens have improved diabetes care for children and adolescents and have led to the definition of new therapeutic goals.

Au cours de ces dernières années, les nouvelles avancées technologiques et thérapeutiques ont marqué la prise en charge du diabète de l'enfant et de l'adolescent amenant ainsi à définir de nouveaux objectifs thérapeutiques.

Health tourism: an opportunity for sustainable development.

In February 2017, the "Programma Mattone Internazionale Salute" (ProMis), that is the Italian Program for Internationalization of Regional Health Systems of the Ministry of Health (MoH), presented the first version of its Position Paper on Health Tourism, which embeds a first shared approach to the recommendations expressed by the European Committee of Regions (CoR) on "Age-Friendly" tourism. The CoR stresses the importance of local and regional authorities in the coordination of multi-sectoral policies such as healthcare, social assistance, transport, urban planning and rural development in relation to the promotion of mobility, security, accessibility of services, including health care and social services. "Age-friendly" tourism is an example of an innovative tourist offer that strives to meet the health needs of the entire "traveling" population, with an integrated and cross-sector approach that involves various organizations operating in sectors such as healthcare, accessibility and transport. The aim of the workshop was to explore the interest of the stakeholders to participate in a systemic action in the field of "health" tourism, and to identify priority implementation areas that offer opportunities to take advantage of validated, innovative experiences that strengthen the accessibility to health and social services in regional, national and international contexts. This effort provides the opportunity to take advantage of aligning the European Structural and Investment Funds (ESIF) to the development of tourism, coherently with the needs and resources of local and regional health authorities.

Early exposure to Aroclor 1254 in vivo disrupts the functional synaptic development of newborn hippocampal granule cells.

Neurogenesis in the dentate gyrus is sensitive to endogenous and exogenous factors that influence hippocampal function. Ongoing neurogenesis and the integration of these new neurons throughout life thus may provide a sensitive indicator of environmental stress. We examined the effects of Aroclor 1254 (A1254), a mixture of polychlorinated biphenyls (PCBs), on the development and function of newly generated dentate granule cells. Early exposure to A1254 has been associated with learning impairment in children, suggesting potential impact on the development of hippocampus and/or cortical circuits. Oral A1254 (from the 6th day of gestation to postnatal day 21) produced the expected increase in PCB levels in brain at postnatal day 21, which persisted at lower levels into adulthood. A1254 did not affect the proliferation or survival of newborn neurons in immature animals nor did it cause overt changes in neuronal morphology. However, A1254 occluded the normal developmental increase in sEPSC frequency in the third post-mitotic week without altering the average sEPSC amplitude. Our results suggest that early exposure to PCBs can disrupt excitatory synaptic function during a period of active synaptogenesis, and thus could contribute to the cognitive effects noted in children exposed to PCBs.

Exposure to endocrine disrupting chemicals and neurodevelopmental alterations.

The developing brain is remarkably malleable as neural circuits are formed and these circuits are strongly dependent on hormones for their development. For those reasons, the brain is very vulnerable to the effects of endocrine-disrupting chemicals (EDCs) during critical periods of development. This review focuses on three ubiquitous endocrine disruptors that are known to disrupt the thyroid function and are associated with neurobehavioral deficits: polychlorinated biphenyls, polybrominated diphenyl ethers, and bisphenol A. The human and rodent data suggesting effects of those EDCs on memory, cognition, and social behavior are discussed. Their mechanisms of action go beyond relative hypothyroidism with effects on neurotransmitter release and calcium signaling.

Apoptosis of Sertoli cells after conditional ablation of murine double minute 2 (Mdm2) gene is p53-dependent and results in male sterility.

Beside its well-documented role in carcinogenesis, the function of p53 family has been more recently revealed in development and female reproduction, but it is still poorly documented in male reproduction. We specifically tested this possibility by ablating Mdm2, an E3 ligase that regulates p53 protein stability and transactivation function, specifically in Sertoli cells (SCs) using the AMH-Cre line and created the new SC-Mdm2(-/-) line. Heterozygous SC-Mdm2(-/+) adult males were fertile, but SC-Mdm2(-/-) males were infertile and exhibited: a shorter ano-genital distance, an extra duct along the vas deferens that presents a uterus-like morphology, degenerated testes with no organized seminiferous tubules and a complete loss of differentiated germ cells. In adults, testosterone levels as well as StAR, P450c17 (Cyp17a1) and P450scc (Cyp11a1) mRNA levels decreased significantly, and both plasma LH and FSH levels increased. A detailed investigation of testicular development indicated that the phenotype arose during fetal life, with SC-Mdm2(-/-) testes being much smaller at birth. Interestingly, Leydig cells remained present until adulthood and fetal germ cells abnormally initiated meiosis. Inactivation of Mdm2 in SCs triggered p53 activation and apoptosis as early as 15.5 days post conception with significant increase in apoptotic SCs. Importantly, testis development occurred normally in SC-Mdm2(-/-) lacking p53 mice (SC-Mdm2(-/-)p53(-/-)) and accordingly, these mice were fertile indicating that the aforementioned phenotypes are entirely p53-dependent. These data not only highlight the importance of keeping p53 in check for proper testicular development and male fertility but also certify the critical role of SCs in the maintenance of meiotic repression.

[Endocrine disruption: a challenge in research, public health and clinical practice]. / La perturbation endocrinienne: entre enjeux de recherche, enjeux de santé publique et enjeux de pratique quotidienne.

Epidemiological and experimental data highlight the fetal and early postnatal life as critical periods for the effects of endocrine disrupting chemicals (EDCs), since exposure to EDCs during these periods can predispose to disease later in life. EDCs' effects include disorders of the reproductive system throughout life (abnormalities of sexual differentiation, infertility or subfertility and some neoplasia) and disorders of energy balance (obesity and metabolic syndrome). They could also influence the development of the cerebral cortex. However, the demonstration of the involvement of a single EDC remains difficult in human since we are virtually exposed to a mixture of several ubiquitous EDCs which are variably persistent in the environment and the body and have lifelong consequences. Moreover, since their dose-response relationship can be non-monotonic, setting a threshold dose for EDCs effects has become meaningless. Pregnant women, newborns and young children appear to be mostly at risk. However, the role of the physician remains difficult and raises several questions: how can we formulate justified, applicable and updated recommendations that are not counterproductive or alarmist...in a society that has to take the necessary steps to regulate production and protect the population?

[Neonatal hyperthyroidism: clinical pattern and therapy]. / L'hyperthyroidie néonatale: clinique et prise en charge thérapeutique.

Neonatal hyperthyroidism is a rare pathology, most often the consequence of Graves' disease in the mother. Around 0.2% of pregnant women have Graves disease and 1 to 2% of newborns of mother with Graves' disease. This article will describe the case of 4 newborns who have been diagnosed and treated in CHU-NDB between 2007 and 2011. The second part will focus on the new recommendations about the management of these young patients from foetal period to birth.

Early neuroendocrine disruption in hypothalamus and hippocampus: developmental effects including female sexual maturation and implications for endocrine disrupting chemical screening.

The timing of puberty has been mainly studied in females for several reasons, including the possible evaluation of a precise timer (i.e. menarcheal age) and concerns with respect to the high prevalence of precocity in females as opposed to males. Human evidence of altered female pubertal timing after exposure to endocrine disrupting chemicals (EDCs) is equivocal. Among the limiting factors, most studies evaluate exposure to single EDCs at the time of puberty and hardly assess the impact of lifelong exposure to mixtures of EDCs. Some rodent and ovine studies indicate a possible role of foetal and neonatal exposure to EDCs, in accordance with the concept of an early origin of health and disease. Such effects possibly involve neuroendocrine mechanisms because the hypothalamus is a site where homeostasis of reproduction, as well as control of energy balance, is programmed and regulated. In our previous studies, pulsatile gonadotrophin-releasing hormone (GnRH) secretion control via oestrogen, glutamate and aryl hydrocarbon receptors was shown to be involved in the mechanism of sexual precocity after early postnatal exposure to the insecticide dichlorodiphenyltrichloroethane. Very recently, we have shown that neonatal exposure to the potent synthetic oestrogen diethylstilbestrol (DES) is followed by early or delayed puberty depending on the dose, with consistent changes in developmental increase of GnRH pulse frequency. Moreover, DES results in reduced leptin stimulation of GnRH secretion in vitro, an effect that is additive with prenatal food restriction. Thus, using puberty as an endpoint of the effects of EDC, it appears necessary to consider pre- and perinatal exposure to low doses and to pay attention to the other conditions of prenatal life, such as energy availability, keeping in mind the possibility that puberty could not only be advanced, but also delayed through neuroendocrine mechanisms.

[How to explore ... congenital isolated hypogonadotrophic hypogonadism]. / Comment j'EXPLORE ... un hypogonadisme hypogonadotrope congénital isolé.

Congenital Isolated hypogonadotropic hypogonadism (CIHH) is caused by an inherited mechanism of impairment of the pituitary-gonadal axis, interfering with gonads' control. Currently, different forms of HHCI with (Kallmann syndrome or KS) or without anosmia-hyposmia are known. There are six forms of KS already described but in several cases no genetic mutation is found. The genetic anomalies already described are: KAL1 (locus Xp23) coding for anosmine-1, KAL-2 or FGFRI (8p11. locus 2 - p11.1) coding for Fibroblast Growth Factor Receptor 1 (FGFR1), KAL4 or PROk2 (locus 3p21.1) and KAL3 or ProKR2 (locus 20p13) coding respectively for the Prokinecitin-2 and its receptor, KAL5 or CHD7 (locus_8q12.1) coding for a chromodomain helicase DNA-binding protein-7 gene (CHD7) and lastly KAL6 or FGF8 (10Q 24 loci) coding for Fibroblast Growth Factor 8. The other genetic anomalies without anosmia are less frequent. These are associated either with Gnrhl gene (8p2-11. 2), GnRHR (4q21.2), GPR54 (19p13),TAC3R or neurokinine receptor 3 (4 q 25), LH (19q13.32) or FSH (11p13). The isolated congenital hypogonadotrophic hypogonadism phenotype is variable depending on gender, the importance of the deficit, and ultimately, according to a specific regulatory mechanism of the axis, affected by an inherited genetic anomaly. In this review, we describe the essential aspects of the different phenotypes and genotypes of HHCI, in order to assess clinicians an early disease's diagnosis and management.

A contactin-receptor-like protein tyrosine phosphatase beta complex mediates adhesive communication between astroglial cells and gonadotrophin-releasing hormone neurones.

Although it is well established that gonadotrophin-releasing hormone (GnRH) neurones and astrocytes maintain an intimate contact throughout development and adult life, the cell-surface molecules that may contribute to this adhesiveness remain largely unknown. In the peripheral nervous system, the glycosylphosphatidyl inositol (GPI)-anchored protein contactin is a cell-surface neuronal protein required for axonal-glial adhesiveness. A glial transmembrane protein recognised by neuronal contactin is receptor-like protein tyrosine phosphatase beta (RPTP beta), a phosphatase with structural similarities to cell adhesion molecules. In the present study, we show that contactin, and its preferred in cis partner Caspr1, are expressed in GnRH neurones. We also show that the RPTP beta mRNA predominantly expressed in hypothalamic astrocytes encodes an RPTP beta isoform (short RPTP beta) that uses its carbonic anhydrase (CAH) extracellular subdomain to interact with neuronal contactin. Immunoreactive contactin is most abundant in GnRH nerve terminals projecting to both the organum vasculosum of the lamina terminalis and median eminence, implying GnRH axons as an important site of contactin-dependent cell adhesiveness. GT1-7 immortalised GnRH neurones adhere to the CAH domain of RPTPbeta, and this adhesiveness is blocked when contactin GPI anchoring is disrupted or contactin binding capacity is immunoneutralised, suggesting that astrocytic RPTP beta interacts with neuronal contactin to mediate glial-GnRH neurone adhesiveness. Because the abundance of short RPTP beta mRNA increases in the female mouse hypothalamus (but not in the cerebral cortex) before puberty, it appears that an increased interaction between GnRH axons and astrocytes mediated by RPTP beta-contactin is a dynamic mechanism of neurone-glia communication during female sexual development.

Effects of in vivo and in vitro administration of ghrelin, leptin and neuropeptide mediators on pulsatile gonadotrophin-releasing hormone secretion from male rat hypothalamus before and after puberty.

The present study aimed to investigate the effects of leptin and ghrelin on pulsatile pulsatile gonadotrophin-releasing hormone (GnRH) secretion in vitro with emphasis on neuropeptide mediators and changes between prepuberty (15 days) and sexual maturity (50 days) in the male rat. When hypothalamic explants were studied 90 min after an intraperitoneal injection of leptin, ghrelin or agouti-related protein (AgRP) at 15 days, the GnRH interpulse interval (IPI) was significantly increased by ghrelin and AgRP and decreased by leptin. At 50 days, an increase in GnRH IPI was also caused by ghrelin and AgRP. When the peptides were directly incubated with the explants, the effects of leptin and AgRP in vitro were consistent with those seen after in vivo administration. By contrast, ghrelin resulted in a reduction of GnRH IPI and this was observed at 15 days only. To delineate the neuropeptide mediators of leptin and the effects of ghrelin in the hypothalamus, various hypothalamic neuropeptides and antagonists were used in vitro. At 15 days, the GnRH IPI was significantly decreased after incubation with cocaine and amphetamine-regulated transcript (CART), alpha-melanocyte-stimulating hormone, corticotrophin-releasing factor (CRF) and neuropeptide Y (NPY). The reduction of GnRH IPI caused by leptin was partially prevented by either an anti-CART antiserum or SHU 9119, a melanocortin MC3/MC4 receptor antagonist or a CRF receptor antagonist. The NPY-Y5 receptor antagonist did not influence the effects of leptin whereas that antagonist totally prevented the decrease in GnRH IPI caused by ghrelin. The ghrelin-induced reduction of GnRH IPI was partially prevented by SHU 9119. When used alone, SHU 9119 or a CRF-receptor antagonist resulted in increased GnRH IPI at 50 days while they had no effects at 15 days. The NPY-Y5 receptor antagonist resulted in increased GnRH IPI at 15 and 50 days. In conclusion, leptin and ghrelin show opposing effects on pulsatile GnRH secretion after administration in vivo whereas they both have stimulatory effects in vitro. Such effects involve consistently the anorectic peptides CART and CRF for leptin that are mainly active at 15 days. The melanocortigenic system appears to mediate the effects of both leptin and ghrelin. The effects of ghrelin also involve NPY receptors and operate effectively before and at sexual maturity.

Female sexual maturation and reproduction after prepubertal exposure to estrogens and endocrine disrupting chemicals: a review of rodent and human data.

Natural hormones and some synthetic chemicals spread into our surrounding environment share the capacity to interact with hormone action and metabolism. Exposure to such compounds can cause a variety of developmental and reproductive detrimental abnormalities in wildlife species and, potentially, in human. Many experimental and epidemiological data have reported that exposure of the developing fetus or neonate to environmentally relevant concentrations of some among these endocrine disrupters induces morphological, biochemical and/or physiological disorders in brain and reproductive organs, by interfering with the hormone actions. The impact of such exposures on the hypothalamic-pituitary-gonadal axis and subsequent sexual maturation is the subject of the present review. We will highlight epidemiological human studies and the effects of early exposure during gestational, perinatal or postnatal life in female rodents.

Leptin effects on pulsatile gonadotropin releasing hormone secretion from the adult rat hypothalamus and interaction with cocaine and amphetamine regulated transcript peptide and neuropeptide Y.

Leptin may act as a negative feedback signal to the hypothalamic control of appetite through suppression of neuropeptide Y (NPY) secretion and stimulation of cocaine and amphetamine regulated transcript (CART). We aimed at studying the effects of leptin, CART and NPY on the hypothalamic control of the pituitary-gonadal system. Pulsatile gonadotropin-releasing hormone (GnRH) secretion was studied in vitro using retrochiasmatic hypothalamic explants from adult rats. In the female, GnRH pulse amplitude was significantly increased by leptin (10(-7) M) and CART (10(-6) M) irrespective of the estrus cycle phase while no such effects were seen in the male. The GnRH interpulse interval was not affected in both sexes. Passive immunoneutralization against CART caused a reduction in GnRH pulse amplitude in the female. A slight but significant increase in GnRH pulse amplitude was caused by NPY (10(-7) M) in the female. However, GnRH pulse amplitude was not affected by a Y5-receptor antagonist (10(-6) M) while the interpulse interval was significantly increased as shown previously in the male. The increase in GnRH pulse amplitude caused by leptin was totally prevented by coincubation with an anti-CART antiserum whereas it was not affected by coincubation with the NPY Y5-receptor antagonist (10(-7) M). In conclusion, leptin and NPY show separate permissive effects on GnRH secretion in the adult rat hypothalamus. In both sexes, NPY is prominently involved in the control of the frequency of pulsatile GnRH secretion through the Y5 receptor subtype. Leptin causes a female-specific facilitatory effect on GnRH pulse amplitude which is mediated by CART and which occurs irrespective of the estrus cycle phase.

Cocaine and amphetamine-regulated-transcript peptide mediation of leptin stimulatory effect on the rat gonadotropin-releasing hormone pulse generator in vitro.

Pulsatile gonadotropin-releasing hormone (GnRH) secretion was studied in vitro using explants of the retrochiasmatic hypothalamus from prepubertal male and female rats. Leptin caused a dose-dependent reduction of the GnRH interpulse interval in both sexes. We studied the effects of cocaine- and amphetamine-regulated transcript (CART) since this peptide was shown recently to mediate the anorectic effects of leptin in the hypothalamus. CART caused a reduction of the GnRH interpulse interval. This effect was prevented using an anti-CART antiserum which could partially overcome leptin stimulatory effects as well. Using hypothalamic explants from Zucker rats homozygous for the leptin receptor mutation ( fa/fa), GnRH pulse frequency was not affected by leptin, while a significant acceleration was caused by the CART-peptide. In conclusion, leptin involves the hypothalamic CART-peptide to stimulate the prepubertal GnRH pulse generator in vitro.

In vitro stimulation of the prepubertal rat gonadotropin-releasing hormone pulse generator by leptin and neuropeptide Y through distinct mechanisms.

Leptin may act as a negative feedback signal to the brain in the control of appetite through suppression of neuropeptide Y (NPY) secretion and stimulation of cocaine- and amphetamine-regulated transcript (CART), a new anorectic peptide. We aimed at studying whether leptin, NPY, and CART have related effects on the hypothalamic control of the pituitary-gonadal system and the developmental changes in NPY and CART effects. Using retrochiasmatic hypothalamic explants from prepubertal 15-day-old male rats, the GnRH interpulse interval (mean +/- SD: 62 +/- 5 min) was significantly reduced by 10(-7) M of leptin (46 +/- 3.3 min) as well as 10(-7) M of NPY (47 +/- 4.4 min) and 10(-6) M of CART (46 +/- 2.7 min), whereas the GnRH pulse amplitude was not affected. The stimulatory effects of different NPY receptor agonists [human PYY 3-36, porcine NPY 13-36, human (D-Trp 32) NPY, porcine (Leu 31 Pro 34) NPY, human pancreatic polypeptide (PP)], as well as the absent effects of rat PP were consistent with the involvement of the Y5-receptor subtype in mediation of NPY effects. Incubation with 10(-7) M of a Y5-receptor selective antagonist prevented the effect of NPY (61 +/- 4 vs. 46 +/- 2 min), whereas leptin and CART effects were not (47 +/- 3 vs. 46 +/- 3 min and 46 +/- 3 vs. 46 +/- 2 min, respectively), suggesting that NPY was not involved in leptin and CART effects. Using an anti-CART antiserum (1:1000), the reduction of GnRH interpulse interval caused by leptin was partially prevented (56.2 +/- 4 vs. 47.9 +/- 3.8 min), whereas the reduction of GnRH interval caused by NPY was not affected (45.9 +/-2.5 vs. 47.8 +/- 3.7). The GnRH interpulse interval was decreased by 10(-7) M of NPY at 5 days (72 +/- 3.8 vs. 91.9 +/- 3.5) as well as at 15 days, whereas such an effect was not observed anymore at 25 and 50 days. Similar effects were observed using 10(-6) M of CART-peptide. Using 10(-6) M of the Y5-receptor antagonist, the GnRH interpulse interval was significantly increased at 15 days (66.6 +/- 2.7 min), 25 days (56.5 +/- 39.9 min), and 50 days (52.5 vs. 38.2 min), whereas no change was observed at 5 days. Using the anti-CART antiserum, a significant increase of GnRH interpulse interval was observed at 25 days only. In conclusion, the stimulatory effects of leptin and NPY on the frequency of pulsatile GnRH secretion before puberty involve two distinct mechanisms. NPY causes acceleration of GnRH pulsatility via the Y5-receptor subtype, which is not involved in leptin effects while the CART is involved in leptin effects on GnRH secretion but not in NPY effects. The reduction of pulsatility by the Y5 antagonist provides evidence of endogenous NPY involvement in the control of GnRH secretion from the time of onset of puberty.

Induction of somatostatin immunoreactivity in cultured ciliary ganglion neurons by activin in choroid cell-conditioned medium.

We have previously shown that the expression of somatostatin-like immunoreactivity in cultured ciliary ganglion neurons is stimulated by a macromolecule found in choroid cell-conditioned medium (ChCM). Here, we present the following evidence that this somatostatin-stimulating activity (SSA) is activin: human recombinant activin induces somatostatin-like immunoreactivity in CG neurons; ChCM induces hemoglobin synthesis in K562 cells, a biological activity characteristic of activin; activin A-specific antibodies recognize a protein in ChCM; cultured choroid cells contain activin RNA; and SSA is inhibited by follistatin, a specific activin-binding protein. Thus, activin is likely to be a neurodifferentiation factor for CG neurons in vivo.

Cloning, expression during development, and evidence for release of a trophic factor for ciliary ganglion neurons.

Ciliary ganglion (CG) neurons undergo a period of cell death during development that may be regulated by the limited availability of trophic factor produced by their target tissues. We have previously reported the purification of a ciliary neurotrophic factor from adult chick sciatic nerve that we called growth promoting activity (GPA). Here we demonstrate that GPA can be purified and cloned from embryonic day 15 (E15) chick eyes, which contain all the target tissues of the CG. Our studies show the following: GPA mRNA is induced in embryonic chick eyes during the period of CG neuron cell death; GPA mRNA is expressed specifically in the layer of the eye that contains the targets of the CG and in primary cultures of smooth muscle cells isolated from the choroid layer of the eye; and biologically active GPA is released from cells transfected with a GPA cDNA.

Rat calmodulin cDNA.

We report the isolation of a clone encoding calmodulin from a rat brain cDNA library; genomic clones were also isolated and partially characterized. The derived amino acid sequence has 100% homology to the published mammalian protein sequences. In rat, we identify two major RNA species of approximately 2.2 and 0.75 kb in length by RNA blot analysis. Furthermore, the mRNA is highly enriched in brain tissue, compared to liver or kidney. A variant (GATAAA) of the putative poly(A) addition signal is observed at the 3' end of one of the mRNA species.