REDUCED DOPAMINERGIC INHIBITION OF THYROTROPHIN RELEASE IN STATES OF PHYSIOLOGICAL HYPERPROLACTINAEMIA

We have tested the hypothesis that physiological puerperal hyperprolactinaemia may be secondary to reduced hypothalamic dopaminergic inhibition of prolactin (PRL) release. Nine post-partum females with physiological hyperprolactinaemia (aged 19–40 years; mean basal PRL±SE, 2099±257 mU/l, range 1002–3762 mU/l) were studied and results compared with fourteen normoprolactinaemic females (basal PRL<400 mU/l; aged 18–36 years). Puerperal hyperprolactinaemic females showed a reduced TSH response to dopamine (DA) receptor blockade with metoclopramide (10 mg i.v.) compared with normal females over a 60-min period following drug administration (total incremental TSH change, mean ±SE, mU/l; 0.5±0.3 v. 3.1±1.0, P<0.005). This finding of reduced dopaminergic inhibition of TSH release in females with physiological puerperal hyperprolactinaemia supports the view that an overall reduction in hypothalamic dopaminergic tone may contribute towards hyperprolactinaemia in post-partum women.     

BIOLOGICAL SIMILARITIES AND DIFFERENCES BETWEEN RATS GENETICALLY DIFFERENT IN ALCOHOL PREFERENCE

This paper is an inventory of some behavioural, biochemicaland pharmacological similarities and differences between twoinbred strains of Wistar rats differing in voluntary consumptionof ethanol, namely: UChA and UChB with low and high preferencesrespectively for ethanol under conditions involving free choicebetween a 10% (v/v) ethanol solution and distilled water. Thefollowing strain differences were observed: ethanol consumption(UChA<UChB); total water consumption (UChA<UChB); solidfood consumption (UChA>UChB); rate of recovery of ethanollabel in expired CO₂ (UChA<UChB); oxidation of ethanol toacetaldehyde by brain homogenates (UChA>UChB); acetaldehydedisposal by brain homogenates (UChA<UChB); ethanol (90 mmol/kg,i.p.) sleeping-time (UChA<UChB); chronic and acute toleranceto ethanol (UChA developed it, whereas UChB did not); lethaldoses of ethanol (UChA>UChB); recovery rate of the labelof gluconate in expired CO₂ (UChA<UChB); recovery rate ofthe label of fructose in expired CO₂ (UChA<UChB); blood-glucoselevel after glucose (1g/kg, i.p.) load (UChA<UChB). No straindifferences were observed in the rate of recovery in expiredCO₂ of the label of the following substrates: acetate, pyruvate,butyrate, citrate, ribose, glycerol, sorbitol, glucose and galactose.     

Unusual Placement of a Pacemaker Pocket

Because of infection and extensive radiation injury to the skin of the chest wall, a dual chamber pacemaker was implanted deep to the clavicle. The wound has been stable and comfortable for 1 year and pacemaker programming has been unimpaired.     

Rotavirus Serology and Breast-Feeding in Young Children in Rural Guinea-Bissau

ABSTRACT. One hundred and forty-four children aged 9–20 months living in 14 villages in a rural area of Guinea-Bissau were examined for circulating rotavirus antibodies twice in a 15-month period. An immunofluorescence technique was used. About 3/4 of the children serocon-verted, independent of age on entering the study. The age-specific proportion of seroposi-tivity increased from 4/40 (10%) at 9–11 months to 26/29 (90%) at 33–35 months of age. All the initially seropositive children retained detectable antibodies to rotavirus. The relative risk of seroconversion was 1.4 times (95% confidence interval 1.0–2.0) more common among children living in villages by the mainroad as compared to those living off the road. Contact rate is probably dependent on population density and mobility but not on age. Breast-feeding, decreasing sharply through the age interval covered by the follow-up (9–35 months), had no apparent influence on seroconversion at the ages concerned.     

Experimental Immune Oophoritis As a Model for Studying the Thymus-Ovary Interaction: 1. Morphological Studies

ABSTRACT: The experimental immune oophoritis (EIO) model was used to study the functional relationship between the ovary and organs of the immune system. EIO was developed in Balb/c mice by twofold subcutaneous injection of saline ovarian extract in complete Freund's adjuvant. The ovary, thymus, and spleen were investigated histologically, histoautoradiographically, and electromicroscopically on days 7, 14, 21, and 28 after immunization. EIO was manifested by massive atresia of follicles and perivascular mononuclear cell infiltration. The appearance of the germinal center like structures in the thymus and increased T cell mitotic activity and B cell stimulation in the spleen pointed out that EIO is mediated both by T and B cells.