Influence of maternal pineal gland on the developmental pattern of neurokinin A (NKA) and substance P (SP) in male-rat-offspring: relationship to the season of the year.

The present study examines the influence of maternal pineal gland on the frontal cortex, striatal and testicular concentrations of the tachykinins, neurokinin A (NKA) and substance P (SP). Control, pinealectomized (PIN-X) and PIN-X plus melatonin-treated (PIN-X + MEL) mother rats were prepared. Male offspring rats were studied at 21, 31 and 60 days of age, during the four seasons of the year. In control-offspring tachykinin concentrations in frontal cortex were found at their highest levels in 21-day-old rats with a moderate decrease up to 60 days of age. This developmental pattern was season-dependent, observed only during summer and fall. Maternal PIN-X or PIN-X + MEL resulted in alterations in the offspring, showing during spring and summer significantly higher concentrations (P < 0.01) and during fall significantly lower concentrations of tachykinins in the frontal cortex (P < 0.05, P < 0.01) as compared to control-offspring. The tachykinin concentration in the striatum of control-offspring showed no major modifications throughout the ages studied in the four seasons of the year. With very few exceptions, PIN-X- and PIN-X + MEL did not alter tachykinin concentrations in striatum. Testicular SP concentrations showed a decrease from 21 to 60 days of age. PIN-X or PIN-X + MEL only caused minor and inconsistent modifications in testicular SP levels. In conclusion, our data clearly indicate for the first time that the maternal pineal gland participates in the regulation of the postnatal tachykinin development in some areas of the central nervous system. This effect was more evident in the frontal cortex than in the striatum and testes.

Seasonal changes of SP and NKA in frontal cortex, striatum and testes in the rat. Role of maternal pineal gland.

The concentrations of neurokinin A (NKA) and substance P (SP), members of tachykinins family, have been studied in all seasons of the year in frontal cortex, striatum and testes of male offspring 21-, 31-, or 60 days old of mother Wistar rats: control, pinealectomized (PIN-X) and pinealectomized + melatonin during pregnancy (PIN- X + MEL) kept under 12h:12h L:D. Control-offspring: in spite of having been kept under constant environmental conditions throughout the year, had marked differences in tachykinin concentrations. The highest tachykinin concentrations in the frontal cortex were found in summer and fall and the lowest in winter and spring. Maternal PIN-X resulted in alterations of this developmental pattern, mainly in PIN-X- and PIN- X + MEL-offspring in which the highest tachykinin concentrations at 21 and 31 days of age were only observed during summer. The alterations were observed up to 60 days of age for both tachykinins, when at this age control-offspring showed similar NKA concentrations. Seasonal variations were still observed in PIN-X- and PIN- X + MEL-offspring. In striatum and testes no mayor modifications throughout the four seasons of the year were found, with very few exceptions. PIN-X did not alter tachykinin concentrations, neither treatment with melatonin did it. In conclusion, our data clearly indicate for the first time that NKA and SP do indeed have seasonal rhythms in frontal cortex and that the maternal pineal gland plays a role in their entrainment already during fetal life.

Valoración de la producción nocturna del catabolito de melatonina, 6-sulfatoximelatonina, durante el climaterio / Evaluation of nocturnal excretion of 6-sulfatoximelatonin during menopause

Introducción: durante el envejecimiento del eje reproductor femenino, el climaterio, el agotamiento folicular en los ovarios origina cambios hormonales entre los cuales se encuentra la melatonina. Sin embargo, el conocimiento de las interacciones entre dichos parámetros dista mucho de ser profundo. Objetivo: valorar el ritmo nocturno de producción de melatonina por medio de la excreción urinaria de 6-sulfatoximelatonina (6-SMEL). Pacientes y método: se realizó un estudio entre 27 mujeres que acudían a las consultas de Ginecología y Menopausia del Hospital Central de Asturias, con una edad de 43-60 años, sanas y sin ningún tipo de tratamiento excepto la terapia hormonal sustitutiva. Ninguna había tenido menopausia quirúrgica. La noche anterior a la correspondiente visita ginecológica recogieron muestras de orina a las siguientes horas: 22:00, 24:00, 04:00, 08:00 y 10:00.Resultados: el estudio del ritmo nocturno de producción de 6-SMEL mostró en el grupo de mujeres menopáusicas el valor más bajo a las 22:00 h, de 475 pg/ml, y el más elevado a las 08:00 h, de 6.063,33 pg/ml, con diferencias estadísticamente significativas: p < 0,01; p < 0,05 a las 22:00 h frente a las 10:00, 04:00 y 08:00 h. En el grupo de menopáusicas que recibían terapia hormonal sustitutiva, el valor más bajo se obtuvo a las 22:00 h, 385 pg/ml, y el valor pico a las 08:00 h, 8.560 pg/ml, con diferencias estadísticamente significativas: p < 0,01 a las 22:00 frente a las 24:00 h; p < 0,05 a las 08:00 frente a las 22:00, 24:00 y 10:00 h. En el grupo de perimenopausia no se demostró estadísticamente un valor pico a ninguna de las horas estudiadas. Conclusión: la terapia hormonal sustitutiva influyó sobre el ritmo nocturno de secreción de 6-SMEL, pero la cantidad total excretada no resultó afectada durante el climaterio (AU)