Forebrain mapping of secretoneurin-like immunoreactivity and its colocalization with isotocin in the preoptic nucleus and pituitary gland of goldfish.

Secretoneurin, a 33-34 amino acid neuropeptide derived from the proteolytic processing of the secretogranin-II precursor protein, is reasonably well conserved in evolution. Goldfish secretoneurin shares >75% similarity overall with other vertebrate secretoneurin sequences. The secretoneurin peptide has numerous functions that include neuroinflammation, neurotransmitter release, and neuroendocrine regulation. A detailed description of the central distribution of secretoneurin immunoreactivity is only known for the rat. Using our polyclonal antibody against the central, conserved core of the secretoneurin peptide we studied the distribution of secretoneurin-like immunoreactivity in the goldfish brain. Secretoneurin immunoreactivity was found in the olfactory bulb, entopeduncular nucleus, preoptic nucleus, lateral part of the lateral tuberal nucleus, posterior periventricular nucleus, nucleus of the posterior recess, the nucleus of the saccus vasculosus, and nucleus isthmi. Secretoneurin-immunoreactive fibers were found in the dorsal part of the dorsal telencephalon, ventral and lateral parts of the ventral telencephalon, periventricular preoptic nucleus, pituitary, and the ventrocaudal aspect of the nucleus of the lateral recess. The most conspicuous secretoneurin immunoreactivity was found in the magnocellular and parvocellular cells of the preoptic nucleus that project to the pituitary. Double-labeling studies indicated coexpression with isotocin, the fish homolog of mammalian oxytocin. Clear colabeling for secretoneurin and isotocin in fibers terminating in the neurointermediate lobe suggests that secretoneurin maybe coreleased with isotocin. Previous work indicates that secretoneurin stimulates the release of luteinizing hormone from the goldfish anterior pituitary. Our findings further support a reproductive role for secretoneurin and related peptides, given the importance of oxytocin family peptides in reproductive behavior in vertebrates.

The secretogranin II-derived peptide secretoneurin stimulates luteinizing hormone secretion from gonadotrophs.

Secretoneurin (SN) is a 33- to 34-amino acid neuropeptide derived from secretogranin-II, a member of the chromogranin family. We previously synthesized a putative goldfish (gf) SN and demonstrated its ability to stimulate LH release in vivo. However, it was not known whether goldfish actually produced the free SN peptide or whether SN directly stimulates LH release from isolated pituitary cells. Using a combination of reverse-phase HPLC and mass spectrometry analysis, we isolated for the first time a 34-amino acid free gfSN peptide from the whole brain. Moreover, Western blot analysis indicated the existence of this peptide in goldfish pituitary. Immunocytochemical localization studies revealed the presence of SN immunoreactivity in prolactin cells of rostral pars distalis of the anterior pituitary. Additionally, we found that magnocellular cells of the goldfish preoptic region are highly immunoreactive for SN. These neurons send heavily labeled projections that pass through the pituitary stalk and innervate the neurointermediate and anterior lobes. In static 12-h incubation of dispersed pituitary cells, application of SN antiserum reduced LH levels, whereas 1 and 10 nM gfSN, respectively, induced 2.5-fold (P < 0.001) and 1.9-fold (P < 0.01) increments of LH release into the medium, increases similar to those elicited by 100 nM concentrations of GnRH. Like GnRH, gfSN elevated intracellular Ca(2+) in identified gonadotrophs. Whereas we do not yet know the relative contribution of neural SN or pituitary SN to LH release, we propose that SN could act as a neuroendocrine and/or paracrine factor to regulate LH release from the anterior pituitary.

Morbilidad y recurrencia de la disección inguino-femoral con incisión limitada en carcinoma epidermoide de vulva / Morbidity and recurrence of the inguino-femoral dissection with limited incision in epidermoid vulvar carcinoma

Tradicionalmente la disección radical ganglionar inguinal ha sido el tratamiento en el carcinoma de vulva, sin embargo, la morbilidad asociada al procedimiento es alta. Recientemente se han propuesto nuevas opciones en el manejo. De tal manera que tanto los procedimientos radicales versus conservadores no han demostrado diferencias en la supervivencia. Objetivo. Comparar la morbilidad y recurrencia tumoral entre dos tipos de abordajes para la disección ganglionar inguino-femoral mediante incisiones cl sicas radicales versus limitadas de tipo conservador. Material y métodos. Retrospectivamente analizamos los expedientes clínicos de pacientes con el diagnóstico de carcinoma epidermoide de la vulva tratados con disección ganglionar con incisión radical versus limitada, durante el periodo de enero de 1986 a diciembre de 1996, en el Instituto Nacional de Cancerología de México (INCan). Se seleccionaron nueve pacientes tratadas con vulvectomía o hemivulvectomía e incisión inguino-femoral limitada (Grupo I), uni o bilateral y 18 pacientes tratadas con vulvectomía o hemivulvectomía con incisiones separadas de la disección ganglionar inguino-femoral pero con incisión radical clásica (Grupo II). Resultados. Durante los 10 años de evaluación, 27 pacientes con carcinoma de vulva fueron identificadas. Para el grupo I el promedio de edad fue de 68.4 años versus 72.5 del grupo II (p= NS). El número de ganglios disecados y recurrencias locales no mostró diferencias con significancia estadística para ambos grupos. La supervivencia para las pacientes del grupo I fue del 66.7 por ciento y 42 por ciento para las del grupo II. Los únicos parámetros con p significativas fueron la frecuencia de bencrosis del colgajo (p= 0.03), infección de la herida quirúrgica (p= 0.05) a favor del grupo I (p= 0.07). Conclusiones. En nuestro Análisis la incisión limitada para realizar la disección ganglionar inguino-femoral ofrece menor morbilidad que la incisión radical clásica, sin repercusión en el control oncológico y supervivencia de las pacientes.