The hypothalamic paraventricular nucleus has a pivotal role in regulation of prolactin release in lactating rats.

The affect of paraventricular nucleus (PVN) lesions on PRL secretory response to suckling was studied in adult female rats. Basal levels of PRL were similar in the control and lesioned groups. Substantial decreases in PRL levels occurred after separation of pups from their mothers in the control as well as lesioned animals. When mothers and pups were reunited, the circulating PRL concentrations of the control groups rose immediately from basal values of 50-100 micrograms/liter to reach peaks of 450-550 micrograms/liter. PVN lesions significantly decreased the suckling-induced rise of PRL levels. Furthermore, PVN lesions abolished the high amplitude, episodic pattern of PRL release in continuously lactating rats. These findings are consistent with the view that PVN neurons produce PRL releasing factor(s), which is (are) required for normal secretory patterns of PRL in lactating rats.

[Prevention of respiratory distress syndrome prior to delivery using steroids]. / Steroidprophylaxe des Atemnotsyndroms vor der Geburt.

Dexamethason in a total dose of 15 mg was given in 125 cases of premature labour 48 hours before delivery to prevent the development of respiration distress syndrome. Clinically, the incidence of RDS was 14,5% (18 cases) in the treated group, while in the control group it was 27,7% (32 cases out of 119). Owing to RDS two prematures died in the treated group, and 14 in the control one. Steroid prophylaxis was applied prenatally with 69 pregnant women at term who were predisposed to give birth to infants developing RDS (retardation, diabetes mellitus, elective section caesareas, etc.). Five neonates developed RDS and one died of hyaline membrane disease. The authors studied the effect of steroids on carbohydrate metabolism and total oestrogen excretion in the urine. From profile examinations of blood sugar it was concluded that no pathological alterations take place in maternal carbohydrate metabolism due to intravenous or intermittent prolonged administration of Dexamethason. After one single large dose (15 mg) of Dexamethason a reduction of 30-40% was noted in total oestrogen excretion. Return to the initial value was noted on the 11th-12th day. No appreciable changes were observed with prolonged intermittently given Dexamethason. On the basis of their observations the authors consider that steroid therapy applied during labour is efficient in preventing neonatal RDS.