Antihypertensive treatment and fetal welfare in essential hypertension in pregnancy: a retrospective survey of experience with various regimes at National Women's Hospital, Auckland, 1970-80.

A series of 184 pregnancies in 161 hypertensive women was classified according to the regimen of antihypertensive treatment used during pregnancy. In 72 pregnancies management was with bed rest alone, attaining a mean gestation of 37.8 +/- 0.4 weeks, a mean birthweight of 2941 +/- 97 g with 38 percent of infants below the 25th percentile. Late deterioration of hypertension with development of proteinuria occurred in 16.6 percent with fetal mortality of 6.9 percent. Antihypertensive therapy involved methyldopa, thiazide diuretics, sympathetic ganglion blockers, hydralazine, beta-adrenergic blockers and the combination of oxprenolol and prazosin. Fetal growth was compared in pregnancies that reached term on the various regimens. Significantly better growth was achieved where debrisoquine plus a thiazide were used (3617 +/- 113 g in six subjects) and oxprenolol/prazosin (3411 +/- 72 g in 14 subjects) compared to 11 comparably hypertensive patients on bed rest alone (2975 +/-87 g). Therapy with the ganglion blocker plus thiazide was complicated by the deterioration of hypertension with proteinuria in 37.2 percent of women; this did not occur in patients receiving oxprenolol/prazosin. Maternal age had no effect on fetal growth, but smoking more than 10 cigarettes per day caused significant growth retardation.

Combined alpha- and beta-adrenoceptor antagonism with prazosin and oxprenolol in control of severe hypertension in pregnancy.

The combination of prazosin (3-21 mg/day) and oxprenolol (60-360 mg/day) was used to treat 25 pregnant women with severe essential hypertension and 19 women with the hypertension-oedema-proteinuria syndrome. In the group with essential hypertension control of blood pressure was sufficient to avoid addition of hydralazine infusions in all but one patient. No patient developed late proteinuria and exacerbation of hypertension once control was established using this regimen. The birthweights of 58 percent of infants were above the 50th percentile of birthweights for the same ages of gestation in normal pregnancies; two intrauterine deaths occurred. In the hypertension-oedema-proteinuria group, blood pressure control was more difficult to sustain, necessitating additional hydralazine infusions in 11 patients. Pregnancy had to be terminated urgently because of progression of the disorder in 13 patients. There were three intrauterine deaths in this series and one infant was lost eight hours after delivery at 27 weeks following five weeks of antihypertensive therapy.

Hormone-induced modifications of free tyrosine in the rat thyroid gland.

The concentrations of free tyrosine in liver, muscle, kidney and thyroid gland were determined in separate groups of rats maintained on a low iodine diet and treated with intraperitoneal injections of thyroxine (T 4), thyrotrophin (TSH) and TSH plus propylthiouracil (PTU). Groups of hypophysectomized rats also were given T 4. Significant changes in tissue tyrosine were generally confined to the thyroid gland. Animals treated with T 4 showed a decrease of mean thyroid tyrosine from 113.3 +/- 17.9 (S.D.) mug/g wet weight of gland to 76.2 +/- 5.7 mug/g (P < 0.01). Although there was little change in content when TSH was given alone, a significant increase in tyrosine levels was observed when TSH plus PTU were administered (P < 0.01). In hypophysectomized rats thyroid tyrosine decreased and was further lowered (to 46.0 +/- 3.1 mug/g; P < 0.05) by T 4 treatment. When tyrosine concentrations were expressed in relation to ribonucleic acid (RNA) or protein content of the assayed gland, all differences in tyrosine content became greater.