[Women and contraception: knowledge and use of contraceptive methods]. / Mulher e anticoncepção: conhecimento e uso de métodos anticoncepcionais.

This article analyzes knowledge and use of contraceptive methods in women ages 10 to 49 years residing in the southern region of the city of São Paulo in 1992. A total of 1,157 childbearing-age women were studied, focusing on variables that might define them as to: knowledge in the use of contraceptive methods and reasons for choosing a given method. We observed that 86% of the women referred knowledge of some contraceptive method, while the most common was the pill (95.3%), followed by condoms (92.6%). Meanwhile, 14% of the interviewees denied knowledge of any contraceptive method. Of the sexually active women (66.4%), 34.9% reported never having used contraceptive methods. Of those who had, 35.3% used the pill, while 42.9% had resorted to sterilization. Only 5.2% used condoms. Despite the high level of knowledge concerning contraceptive methods, especially oral contraceptives and condoms, we observed limited use of same as compared to the high sterilization rate around the age of 27, thus leaving contraception limited to the pill and female sterilization.

Decreased basal and acute insulin-stimulated effect on the uptake of glucose and amino acid in vitro by thyroid glands from streptozotocin-diabetic rats.

Since experimental diabetes in rats and mice is associated with impairment of several aspects of thyroid function, we determined glucose and amino acid uptake in vitro by isolated thyroid glands from normal and streptozotocin-diabetic rats. Adult male Wistar rats weighing 150-200 g were used. Diabetes was induced by intraperitoneal injection of streptozotocin (STZ, 65 mg/kg body weight) and after five days only rats with blood glucose levels higher than 250 mg/dl were used. The thyroid glands were preincubated in Krebs-Ringer bicarbonate buffer in the presence or absence of insulin (0.7 nM to 7 muM) for 90 min and then incubated with the same concentration of the hormone or its vehicle plus 0.2 microCi of [1-14C]-2-deoxy-D-glucose ([14C]DG) or [1-14C] methylaminoisobutyric acid ([14C]MeAIB) for 15 to 180 min. The uptake of [14C]DG or [14C]MeAIB by the thyroid glands of normal rats increased as a function of incubation time, and the presence of insulin (7 microM) induced a significant increase of labelled DG from 3.30 +/- 0.11 to 4.16 +/- 0.12 and of labelled meAIB from 1.79 +/- 0.06 to 3.10 +/- 0.17 tissue/medium ratio (T/M) and after 45 min of incubation. The lowest concentration of insulin that increased both [14C]DG and [14C]MeAIB transport was 7 nM. Thyroid glands from STZ rats exhibited lower basal values of [14C]DG (4.03 +/- 0.11 T/M) or [14C]MeAIB uptake (1.05 +/- 0.05 T/M) than glands from normal rats (4.62 +/- 0.13 and 1.70 +/- 0.08 T/M, respectively). Insulin produced a stimulatory effect on the transport of both substrates in STZ rats. However, the maximal stimulating concentration of the hormone did not restore [14C]DG and [14C]MeAIB uptake to control values (4.89 +/- 0.17 in STZ rats versus 5.44 +/- 0.17 T/M in controls for [14C]DG, and 1.51 +/- 0.11 in STZ rats versus 2.19 +/- 0.10 T/M in controls for [14C]MeAIB). These results indicate that insulin exerts a direct action on the thyroid gland, and its absence or reduction affects thyroid metabolism, contributing, at least in part, to the abnormality in thyroid function associated with diabetes mellitus.

Decreased basal and acute insulin-stimulated effect on the uptake of glucose and amino acid in vitro by thyroid glands from streptozotocin-diabetic rats

Since experimental diabetes in rats and mice is associated with impairment of several aspects of thyroid function, we determined glucose and amino acid uptake in vitro by isolated thyroid glands from normal and streptozotocin-diabetic rats. Adult male Wistar rats weighing 150-200 g were used. Diabetes was induced by intraperitoneal injection streptozotocin (STZ, 65 mg/kg body weight) and after five days only rats with blood glucose levels higher than 250 mg/dl were used. The thyroid glands were preincubated in Krebs-Ringer bicarbonate buffer in the presence or absence of insulin (0.7 nM to 7 muM) for 90 min and then incubated with the same concentration of the hormone or its vehicle plus 0.2 muCi of [l-l4C]-2-deoxy-D-glucose ([l4C]DG) or [l4C] methylaminoisobutyric acid ([l4C]MeAIB) for 15 to 180 min. The uptake of [l4C]DG or [l4C]MeAIB by the thyroid glands of normal rats increased as a function of incubation time, and the presence of insulin (7 muM) induced a significant increase of labelled DG from 3.30 ñ 0.11 to 4.16 ñ O.12 and of labelled MeAIB from 1.79 ñ 0.06 to 3.10 ñ 0.17 tissue/medium ratio (TIM) after 45 min of incubation. The lowest concentration of insulin that increased both [l4C]DG and [l4C]MeAIB transport was 7 nM. Thyroid glands from STZ rats exhibited lower basal values of [l4C]DG (4.03 ñ 0.11 T/M) or [l4C]MeAIB uptake (1.05 ñ 0.05 T/M) than glands from normal rats (4.62 ñ 0.13 and 1.70 ñ 0.O8 T/M, respectively). Insulin produced a stimulatory effect on the transport of both substrates in STZ rats. However, the maximals stimulating concentration of the hormone did not restore[l4C]DG and [l4C)MeAIB uptake to control values (4.89 + O.17 in STZ rats versus 5.44 ñ 0.17 T/M in controls for [l4C]DG, and 1.51 ñ 0.11 in STZ rats versus 2.19 ñ 0.10 T/M in controls for [l4C]MeAIB). These results indicate that insulin exerts a direct action on the thyroid gland, and its absence or reduction affects thyroid metabolism, contributing, at least in part, to the abnormality in thyroid function associated with diabetes mellitus.

Isolation, purification and primary structure of insulin from the turtle Chrysemys dorbigni.

Insulin A and B chains from pancreas of the turtle Chrysemys dorbigni have been purified to homogeneity, and their primary structures have been determined. The sequence of the A chain is G-I-V-E-Q-C-C-H-N-T-C-S-L-Y-Q-L-E-N-Y-C-N, and that of the B chain is A-A-N-Q-H-L-C-G-S-H-L-V-E-A-L-Y-L-V-C-G-E-R-G-F-F-Y-S-P-K-A. The amino acid sequence of Chrysemys insulin is identical to that of another turtle (Pseudemys scripta), the chicken, and turkey. When compared with alligator insulin, it has three conservative substitutions in the B chain. However, there are seven substitutions when compared with the insulin of the rattlesnake.

In vitro effect of insulin on the uptake of glucose and alpha-aminoisobutyric acid in the thyroid gland of the turtle (Chrysemys dorbigni).

The presence of specific insulin binding sites in the thyroid gland of the turtle Chrysemys dorbigni has been previously reported. The purpose of the present work was to investigate the probable action of insulin on the uptake of [14C]deoxy-D-glucose ([14C]DG) and [14C]alpha-aminoisobutyric acid ([14C]AIB) in turtle (C. dorbigni) thyroid glands in vitro. Thyroid fragments (+/- 40 mg) were incubated at 25 degrees in Krebs-Ringer-bicarbonate buffer containing 0.2 microCi of [14C]DG or [14C]AIB without or with bovine insulin at different periods of time. The uptake of [14C]DG and [14C]AIB increased with incubation time. The presence of insulin (7 x 10(-6) M) in the incubation medium during 240 min did not modify the [14C]DG uptake. However if the thyroid fragments were previously incubated with insulin (60 min) and then incubated (240 min) with the same concentration of the hormone, the [14C]DG uptake was markedly increased. This stimulatory effect of insulin was dose-dependent. In similar experimental conditions, insulin also produced a significant increase in the uptake of [14C]AIB. Therefore, these findings strongly support the hypothesis that insulin might exert a direct action on the thyroid function.

Immunohistochemical localization of insulin-like materials in antral gastric mucosa and intestinal epithelial cells of the turtles Chrysemys dorbigni and Phrynopshilarii

Immunoreactive insulinwas demonstrated immunohistochemically with antibodies to human and porcine insulin by the avidin-biotin-peroxidase complex method in open-type gastrointestinal cells from sections of the antral stomach and of the upper, midle and lower intestine of the turtles Chrysemys dorbigni and Phrynops hilarii.In both species the concentration of cells positive for insulin-like material was higher in the gastric antrummthan in the gut.The localization of insulin-like material in gastrointestinal mucosal cells of turtles is an unusual finding among vertebrates, because the insulin-containing cells migrate from the mucosal epithelium of the intestine early in vertebrate evolution to the acinar pancreas.The chemical nature of the gastrointestinal insulin-like material and its physiological role remainm to be determined

Immunohistochemical localization of insulin-like materials in antral gastric mucosa and intestinal epithelial cells of the turtles Chrysemys dorbigni and Phrynops hilarii.

Immunoreactive insulin was demonstrated immunohistochemically with antibodies to human and porcine insulin by the avidin-biotin-peroxidase complex method in open-type gastrointestinal cells from sections of the antral stomach and of the upper, middle and lower intestine of the turtles Chrysemys dorbigni and Phrynops hilarii. In both species the concentration of cells positive for insulin-like material was higher in the gastric antrum than in the gut. The localization of insulin-like material in gastrointestinal mucosal cells of turtles is an unusual finding among vertebrates, because the insulin-containing cells migrate from the mucosal epithelium of the intestine early in vertebrate evolution to the acinar pancreas. The chemical nature of the gastrointestinal insulin-like material and its physiological role remain to be determined.

Insulin binding sites and action in the adrenal glands from normal and streptozotocin diabetic rats.

Insulin binding to rat adrenal glands was studied in vivo by i.v. injection of 125I-insulin either alone or together with an excess of unlabelled hormones (insulin, glucagon, prolactin, or growth hormone). In addition, isolated glands from normal or streptozotocin diabetic rats (STZ) were incubated in vitro with 125I-insulin and varying concentrations of unlabelled insulin. Both experiments showed specific binding sites in the adrenal glands. Furthermore the glands from diabetic rats bound more insulin than the glands from controls. The insulin stimulatory effect on the deoxyglucose (14C-DG) uptake was examined in isolated glands from normal and STZ rats. Adrenal glands from control rats exhibited higher basal values of 14C-DG uptake than glands from STZ rats. Insulin induced a stimulatory effect on the 14C-DG transport in glands from both control and diabetic rats. Adrenal glands from STZ rats responded much earlier to exogenous insulin, however the maximal stimulating concentration of the hormone did not restore the 14C-DG uptake to control values. The lowest concentration of insulin that increased the 14C-DG transport was 3 X 10(-8) M. The adrenal gland must be considered a target organ for insulin by both criteria, insulin specific binding and stimulatory action on the deoxyglucose transport.