Hypothalamic KiSS1/GPR54 gene expressions and luteinizing hormone plasma secretion in morphine treated male rats

Background: The inhibitory effects of morphine and the stimulatory influence of kisspeptin signaling have been demonstrated on gonadotropin releasing hormone [GnRH]/luteinizing hormone [LH] release. Hypothalamic kisspeptin is involved in relaying the environmental and metabolic information to reproductive axis. In the present study, the role of kisspeptin/ GPR54 signaling system was investigated on relaying the inhibitory influences of morphine on LH hormone secretion

Materials and Methods: In this experimental study, 55 wistar male rats weighing 230-250 g were sub-grouped in 11 groups [in each group n=5] receiving saline, kisspeptin [1 nmol], peptide234 [P234, 1 nmol], morphine [5 mg/kg], naloxone [2 mg/kg], kisspeptin/P234, morphine/naloxone, kisspeptin/morphine, kisspeptin/naloxone, P234/morphine or P234/naloxone respectively. Blood samples were collected via tail vein. Mean plasma [LH] concentrations and mean relative KiSS1 or GPR54 mRNA levels were determined by radioimmunoassay [RIA] and real time reverse transcriptase-polymerase chain reaction [RT-PCR], respectivwely

Results: Morphine significantly decreased mean plasma LH concentration and mean relative KiSS1 gene expression compared to saline; while it did not significantly decrease mean relative GPR54 gene expression compared to saline. Naloxone significant increased mean LH level and mean relative KiSS1 gene expression compared to saline; while it did not significantly increase mean relative GPR54 gene expression compared to saline. Injections of kisspeptin plus morphine significantly increased mean LH concentration compared to saline or morphine, while simultaneous infusions of them significantly declined mean plasma LH level compared to kisspeptin. In kisspeptin/naloxone group mean plasma LH level was significantly increased compared to saline or naloxone. Co-administration of P234/morphine significantly decreased mean LH concentration compared to saline

Conclusion: Down regulation of KiSS1 gene expression may be partly involved in the mediating the inhibitory effects of morphine on reproductive axis

Orexin decreases aromatase gene expression in the hypothalamus of androgenized female rats

Background: Orexin is a hypothalamic orexigenic neuropeptide, which third cerebral injection of it mainly exerts inhibitory effects on reproductive functions. It increases significantly the Aromatase [Cyp19] gene expression in the hypothalamus of male rats. Aromatase is an enzyme which converts androgens to estradiol in the hypothalamus of rats. Prenatal or neonatal exposure of females to testosterone masculinizes the pattern of Cyp19 mRNA levels in adulthood. In the present study the effects of central injections of orexin-A on hypothalamic Cyp19 gene expression of adult female rats were investigated, while they had been androgenized on third day of postnatal life

Materials and Methods: In this experimental study, twenty female Wistar rats received subcutaneous injections of testosterone propionate [50 microg/100 microl] on their third day of postnatal life. Adult androgenized rats weighing 180-220 g, received either 3 microl saline or one of 2, 4 or 8 microg/3 microl concentration of orexin via third cerebral ventricle. Five non-androgenized rats, as control group, received intra cerebral ventricle [ICV] injection of 3 microl saline. The hypothalamuses were dissected out and mean Cyp19 mRNA levels were determined by semi-quantitative real time-polymerase chain reaction [PCR] method. Data were analyzed by unpaired t test and one-way ANOVA using SPSS software, version 16

Results: Mean relative Cyp19 mRNA level was significantly increased in the hypothalamus of androgenized compared to non-androgenized female rats. Central injec- tions of 2, 4 or 8 microg/3 microl orexin decreased significantly the hypothalamic Cyp19 mRNA level of androgenized rats compared to androgenized-control groups

Conclusion: The results suggested that the orexin may exert inhibitory effects on the gene expression of Cyp19 in the hypothalamus of neonatal androgenized female rats in adulthood

Morphine attenuates testosterone response to central injection of kisspeptin in male rats

Background: Kisspeptin and naloxone stimulate the reproductive axis while morphine inhibits its function. We have investigated the effect of central injection of kisspeptin-10 on mean plasma testosterone concentration in morphine or naloxone pretreated rats

Materials and Methods: In this experimental study, 60 male Wistar rats that were divided into 12 groups [n=5 per group] received saline, kisspeptin [1 nmol, ICV], naloxone [2 mg/kg, subcutaneously], morphine [5 or 10 mg/kg, sc] or co-administrations of kisspeptin, morphine and naloxone at 09:00 - 09:30. In the co-administrated groups, kisspeptin was injected 15 minutes following morphine or naloxone injections. Blood samples were collected 60 minutes following injections via the tail vein. Plasma testosterone concentration was measured by a rat testosterone ELISA kit

Results: Central injection of kisspeptin or subcutaneous injection of naloxone significantly increased the mean plasma testosterone concentration compared to saline while subcutaneous injections of different doses of morphine [5 or 10 mg/kg] significantly decreased testosterone compared to saline. The results revealed that morphine significantly attenuated the testosterone increase after kisspeptin injection compared to kisspeptin while a stimulatory additive effect was observed in the kisspeptin/naloxone group compared to either naloxone or kisspeptin

Conclusion: Morphine and kisspeptin systems may interact with each other to control the hypothalamic-pituitary-gonadal [HPG] axis

rare case of klinefelter syndrome patient with quintuple mosaic karyotype, diagnosed by GTG-banding and FISH

Klinefelter syndrome [KS] is the most common sex chromosomal disorder in men. Most of these patients show the 47, XXY karyotype, whereas approximately 15% of them are mosaics with variable phenotype. A 39-year-old male investigated for primary infertility, was clinically normal with small firm testes and elevated levels of FSH, LH and low level of testosterone. Total azoospermia was confirmed on semen analysis. Testicular histopathology revealed no spermatogenesis and absence of germ cells. Karyotype from whole blood culture showed cells with 47, XXY/46, XX/ 45, X/48, XXXY/ 46, XY mosaicism. The predominant cell line was 47, XXY [83.67%]. This was confirmed by fluorescence in situ hybridization [FISH]. Also the presence of a small population of cells with the 48, XXXY and 45, X karyotypes was detected by FISH. This case illustrates the utility of FISH as an adjunct to conventional cytogenetics in assess the chromosome copy number in each cell line of a mosaic