Effect of pinealectomy and melatonin treatment during pregnancy on the sexual development of the female and male rat offspring

Abstract

Sexual development of female and male rat offspring of control, pinealectomized (PIN-X) or melatonin (MEL 250 micrograms/100 g body wt)-treated mother rats during pregnancy was studied. Newborns were studied at the following phases of sexual development: neonate (5 days old), infantile (15 days old), juvenile (25 and 30 days old) and pubertal phase (55 days). In female offspring, MEL treatment during pregnancy significantly increased plasma luteinizing hormone (LH) in 15- and 25-day-old rats; however, at the end of the prepubertal period (30 days) the concentration of plasma LH decreased significantly as compared to control rats. This hormonal pattern was different from that observed in offspring of control and PIN-X rats, which had low LH levels at 25 days of age and higher LH levels at 30 days of age. Follicle-stimulating hormone (FSH) did not vary significantly among the three groups. Plasma prolactin levels were affected by PIN-X of the mother, showing significantly higher levels in the 5-day-old offspring than in the controls; plasma prolactin levels were also affected by MEL treatment of the mother, producing hyperprolactinemia in the 30-day-old female offspring. In male offspring, sexual development in control male rats progressed rapidly with significantly increased LH and FSH levels at 25 and 30 days compared to those measured during the neonatal and infantile periods.(ABSTRACT TRUNCATED AT 250 WORDS)

The absence of maternal pineal melatonin rhythm during pregnancy and lactation impairs offspring physical growth, neurodevelopment, and behavior

“…In addition to the importance of melatonin to embryo development, the absence or the administration of melatonin to pregnant animals seem to be able to differentially influence male and female offspring development, in accordance to the present data (López et al, 1995). Similar findings have been reported in intrauterine programming of metabolic function for high-protein diet (Thone-Reineke et al, 2006), obesity (Lecoutre et al, 2016) and glucocorticoid exposure (O'Regan et al, 2004).…”

Melatonin therapy for circadian rhythm sleep disorders in children with multiple disabilities: what have we learned in the last decade?

“…55 Alteration of sexual maturation and of reproductive hormone levels were seen among the offspring of pregnant rats but not in humans. 56 Large doses, up to 300mg daily, were given to healthy women in one study as a contraceptive, without shortor long-term adverse effects. 57 Based on a small, uncontrolled case report, 58 caution was advised in the use of MT for children with epilepsy, suggesting that pharmacological doses of this hormone had proconvulsive properties.…”

Seasonal variations of Substance P in the striatum of the female rat are affected by maternal and offspring pinealectomy

“…There is evidence that the maternal pineal gland influenced prenatal and postnatal development of offspring, and suppressed the incidence of spontaneous malformations [17]. An influence of the maternal pineal gland on postnatal ontogeny of the hormones involved in the neuroendocrine-reproductive axis was found in both female and male developing rats [11].…”