Modification of GABAergic activity and thyrotropin secretion in male rats

The effect of GABA on basal and stimulated TSH secretion was studied in male rats. The effects of drugs on basal TSH levels were not consistent. Muscimol(0.5 mg/kg subcutaneously, but not 2 mg/kg) increased whereas baclofen (10 mg/kg intraperitoneally), amino-oxyacetic acid (AOAA, 20 mg/kg intraperitoneally) and bicuculline (2 mg/kg intraperitoneally, but not 1 or 4 mg/kg) decreased basal TSH concentrations. Muscimol, AOAA and baclofen dose-dependently reversed the TSH cold-response, as did a large dose of di-n-propylacetate (DPA, 400 mg/kg intraperitoneally) and 500 mg/kg (but not 50, 100 or 1500 mg/kg intraperitoneally) of GABA itself. Bicuculline was not effective alone. Neither did it modify the effects of muscimol, AOAA and GABA on the cold-stimulated TSH response. None of the drugs studied (AOAA, GABA, bicuculline) modified TRH-induced (100 ng intraperitoneally) TSH-response. GABA injected into the third ventricle (5-50 microgram/rat) or into the medial basal hypothalamus (MBH, 5 microgram/rat) had no effect on the basal TSH levels. However, the TSH cold-response was inhibited when GABA (5 microgram/rat) was infused into the MBH but not when it was infused into the third ventricle (5-50 microgram/rat). The results suggest that GABAergic pathways may have an inhibitory effect on the stimulated TSH secretion in male rats. The locus of this inhibition is not situated in the anterior pituitary, but possibly in the MBH.     

Radioimmunoassay for Doxepin and Desmethyldoxepin

Abstract: A simple and sensitive radioimmunoassay (RIA) for the determination of doxepin and desmethyldoxepin in plasma or serum has been developed using a previously reported antiserum to the tricyclic anti-depressants. Before assay, doxepin is separated from desmethyldoxepin with selective extraction at different pH values enabling each to be measured specifically. ³H-imipramine is used as tracer. By using the extraction procedure doxepin and desmethyldoxepin concentrations can be measured down to 9 nmol/l from a 0.1 ml sample. If necessary, sensitivity can be doubled by taking a 0.2 ml sample to the extraction. Recoveries of doxepin and desmethyldoxepin were quantitative when the drugs were added at different concentrations to normal, pooled human plasma and the inter- and intra-assay coefficients of variation did not exceed 9%. The concentrations obtained from patient samples by the present RIA correlated well with those by high-pressure liquid chromatography. The RIA was also shown to be useful in pharmacokinetic single dose studies with doxepin.     

Early puerperal insertions of Copper-T-200

The Copper-T-200 (CuT-200) was inserted after delivery at term in 197 women on the day preceding discharge from the hospital. The majority of the insertions were done on day 5 or 6 after delivery. Every subject in the study was followed more than 12 months. The insertions were well tolerated; no perforations or serious side effects occurred. During the first year of use, only 9 infections were recorded. The first segment pregnancy rate (7.2) and expulsion rate (14.8) were significantly higher and the continuation rate, 69.5, lower than that obtained with the same device inserted in postmenstrum women. The expulsions were mainly partial (11.1), and were discovered during the first and second months postpartum. The postpartum insertions were found to be safe and well accepted. The high pregnancy and expulsion rates make the CuT-200 an unsuitable IUD in postpartum programs where follow-up is not adequate and early removals of partially expelled or displaced devices is not possible.     

Surgical treatment of hernia through the foramen of Morgagni.

A series of 25 surgically treated patients with the Morgagni type of diaphragmatic hernia is presented. Twenty-two of the patients were female and three were male. The hernia was on the right side in all of them. Five of the patients had symptoms which were predominantly gastrointestinal. The remainder of the patients were asymptomatic and were admitted to hospital because of an abnormal finding at chest X-ray. All but one were operated transthoracically. In one case an abdominal approach was used because cholecystectomy was performed simultaneously with the hernial repair. In 3 cases the hernail sac contained a portion of transverse colon and in 9 cases, omentum. In 12 there was an accumulation of adipose tissue in the hernial sac, and in 2 cases it was empty when operated. There were no serious complications and no mortalities.     

Increased Serum Concentrations of Lactic, Pyruvic and Uric Acid and Bilibubin After Postoperative Xylitol Infusion

Xylitol has been suggested as a more advantageous calory source for intravenous administration than glucose in certain clinical situation, but the general suitability of intravenous xylitol infusion has not been confirmed. Thirty-middle-aged women were infused with 100 g of xylitol as postoperative fluid therapy after gynaecological laparotomy and general anaesthesia. Another 10 women received 50 g of glucose in a similar manner and served as a reference group. Infusion of xylitol both at the rate of 0.25 g/kg/h (1000 ml 10% xylitol in approx. 8 h) and 0.5 g/kg/h (1000 ml 10% xylitol in approx. 4 h) caused a distinct increase in the serum concentrations of lactic acid, pyruvic acid, and uric acid; such an increase was not seen with glucose infusion. The faster infusion of xylitol also distinctly increased serum bilirubin concentrations. Because of the possibility of lactic acidosis and urate deposits in kidneys, infusion of 100 g or more of xylitol at a rate of 0.25 g/kg/h or faster is not safe for postoperative fluid therapy in routine clinical work.     

Drugs, alcohol and driving.

Driving a car is a complex psychomotor and perceptual task which is subject to impairment by many factors. Several workers have studied the potential effects of drugs and alchol in crash production by epidemiological and laboratory studies. Both types of studies have yielded useful data but their limitations must be borne in mind when applying the results in pratice. Alcohol is obviously the most common single cause of traffic accidents. A progessively increased risk with increasing blood alcohol levels is well documented; fatigue and/or drugs increase this risk. Drugs are related much more infrequently to traffic accidents although on the basis of statistics, there is a potential risk with drug use. However, drugs alone are not as important as alcohol. The most significant drugs as regards driving risk are obviously certain antianxiety agents, hypnotics, stimulants, hallucinogens, marihuana, lithium and narcotic analgesics, as well as ganglionic blocking agents, insulin and sulphonylurea derivates. Patients should not drive after taking these drug until they are objectively fully alert and capable. Anticholinergics, antihistamines, antidepressants, antipsychotics, phenybutazone, indomethacin, alpha-methyldopa, and beta-blockers may in some cases cause central side effects (e.g. drowsiness) strong enough to affect driving performance. After starting therapy with these drugs, or after a significant change in dose, driving should be avoided until it is known that unwanted effects do not occur. Psychotropic drugs may enhance the deleterious effect of alcohol, and with most hypnotics there is still an effect the next morning. Some drugs (e.g. anticonvulsants or antiparkinsonian drugs) may make driving safer, but the disease (epilepsy, Parkinsonism, cardiovascular diseases, psychic disorders, etc.) ofter precludes driving. Clinicians should warn their patients about an impairment of driving skills if this is likely to occur due to the drug or the illness concerned.