propylthiouracil and Hypertension

Topics: Acetaminophen; Adenoidectomy; Adenoids; Analgesics, Non-Narcotic; Analgesics, Opioid; Antihypertensive Agents; Antithyroid Agents; Atenolol; Child; Fentanyl; Follow-Up Studies; Graves Disease; Humans; Hydrocodone; Hypertension; Male; Palatine Tonsil; Propylthiouracil; Sleep Apnea Syndromes; Tachycardia; Thyroid Gland; Tonsillectomy

Although low thyroid function is known to have detrimental effects on the cardiovascular system, including microvascular impairment, little is known about the pathophysiologic consequences of hypothyroidism in the background of hypertension.. Hypothyroidism was induced in female spontaneously hypertensive heart failure (SHHF) rats by treatment with propylthiouracil (PTU) for 6 months. Untreated SHHF and normotensive Wistar Furth (WF) rats served as controls. In terminal experiments, heart weight, echocardiographic measurements, hemodynamics, and arteriolar morphometry were performed. Left ventricular internal diameter in systole and diastole were increased and wall thickness, ejection fraction, heart rate, systolic blood pressure, and +/-dP/dt were significantly decreased in the treatment group. Surprisingly, there were no observed differences in arteriolar density among the 3 groups.. As expected, PTU treatment of SHHF rats led to systolic dysfunction and chamber dilation. However, PTU treatment did not lead to arteriolar loss as previously observed in normotensive rats treated with PTU. These finding suggest that induced hypothyroidism leads to detrimental changes in SHHF rats, but the overall effects were no worse than those previously observed in normotensive rats treated with PTU.

Topics: Animals; Female; Heart Failure; Hemodynamics; Hypertension; Hyperthyroidism; Microcirculation; Myocardium; Propylthiouracil; Rats; Rats, Wistar; Thyroid Gland; Time Factors

Caudal arterial lesions form spontaneously with age in the male Wistar rat and are characterized by a break in the internal elastic lamina (IEL), with associated damage to endothelium and underlying smooth muscle cells followed by rapid repair. Such lesions have been studied under conditions of hypercholesterolaemia. Diet-induced hypercholesterolaemia did not enhance the formation of these lesions compared to age-matched control rats. Lesioned areas of caudal arteries from hypercholesterolaemic rats showed marked or slight focal lipid deposits depending upon their location along the artery. Studies in rats of different ages suggest that the majority of lipid probably accumulates during the phase of lesion repair and that the absence of the IEL per se does not appear to be responsible for the lipid accumulation. The effect of hypertension associated with hypercholesterolaemia on caudal arterial lesions was studied using DOCA salt-Wistar and spontaneously hypertensive rats. The association of these two factors did not increase lesions either in the caudal artery or in the renal artery studied for comparison. In caudal artery the number of fatty lesions appeared to be related more to the level of cholesterolaemia than to blood pressure. The extent of lipid accumulation within lesions in the caudal artery appears not to correlate with that in the renal artery, demonstrating the importance of local factors.

Topics: Animals; Arteries; Body Weight; Cholesterol; Diet, Atherogenic; Dietary Fats; Elastic Tissue; Hypercholesterolemia; Hypertension; Lipid Metabolism; Male; Propylthiouracil; Rats; Rats, Inbred Strains; Rats, Mutant Strains; Renal Artery; Tail

The present study was undertaken to seek ultrastructural changes in the thyroid gland of the spontaneously hypertensive rat which would contribute to the understanding of previously reported abnormalities in thyroid function. Light and electron microscopic observations and measurements of plasma T3 and systolic blood pressure were recorded from a colony of Wistar Kyoto rats (WKY) and of spontaneously hypertensive rats (SHR). The systolic blood pressure of SHR was significantly higher than that of WKY but the plasma T3 levels of the two groups did not differ significantly. After administration of propylthiouracil (PTU), serum T3 levels and systolic pressure of both groups decreased. The size of the thyroid follicles in SHR was highly variable throughout the gland, and the colloid contained unevenly dense areas and cell debris. The follicular cells contained slightly dilated rough surfaced endoplasmic reticulum (ER) and numerous pleomorphic bodies of uneven density. After treatment with PTU, the vessels between the follicles of SHR did not become as dilated as those in WKY but the fine structure of follicular cells in SHR was similar to that of WKY and was characteristic of the typical thyroid response to PTU administration. We suggest that the thyroid in SHR does not respond adequately to the elevated TSH levels reported to be present in these animals, although it can respond to the highly elevated TSH levels which occur with PTU administration. This impairment most probably involves defects in synthesis and/or secretion of thyroid hormones in response to TSH stimulation.

Topics: Animals; Hypertension; Propylthiouracil; Rats; Thyroid Gland; Thyrotropin; Triiodothyronine

Topics: Animals; Blood Pressure; Body Weight; Desoxycorticosterone; Female; Hypertension; Hypertension, Renal; Iodine Radioisotopes; Male; Organ Size; Pituitary Gland; Propylthiouracil; Rats; Species Specificity; Thyroid Function Tests; Thyroid Gland; Thyroxine

Topics: Animals; Aorta; Desoxycorticosterone; Dinitrophenols; Hypertension; Hypothyroidism; Lipoprotein Lipase; Male; Myocardium; Organ Size; Oxygen Consumption; Propylthiouracil; Rats

Topics: Adrenocorticotropic Hormone; Blood Pressure; Cortisone; Endocrinology; Hypertension; Hypophysectomy; Luteinizing Hormone; Oxytocin; Pharmacology; Pituitary Gland; Pituitary Gland, Posterior; Propylthiouracil; Rats; Research; Testosterone; Thyrotropin; Thyroxine; Vasopressins

Topics: Adolescent; Child; Cystic Fibrosis; Down Syndrome; Humans; Hypertension; Intelligence Tests; Models, Theoretical; Peptic Ulcer; Pharmaceutical Preparations; Pharmacogenetics; Pharmacology; Poisons; Propylthiouracil; Quinine; Saliva; Taste

Topics: Adrenocorticotropic Hormone; Desoxycorticosterone; Epinephrine; Hydrocortisone; Hypertension; Lipid Metabolism; Lipids; Methyltestosterone; Pineal Gland; Propylthiouracil; Serotonin; Thyroxine

Topics: Animals; Hypertension; Hypertension, Renal; Propylthiouracil; Rats; Thiouracil; Thyroid Function Tests; Thyroid Gland; Thyroidectomy; Viscera

Topics: Animals; Hypertension; Propylthiouracil; Rats; Sodium Chloride; Sodium Chloride, Dietary; Thiouracil

Topics: Adrenal Gland Diseases; Animals; Hypertension; Propylthiouracil; Rats; Regeneration; Thiouracil

Topics: Animals; Hypertension; Hypertension, Renal; Maintenance; Propylthiouracil; Rats; Thiouracil