Asunto(s)
Peso al Nacer , Encéfalo/embriología , Ácidos Grasos Esenciales/análisis , Retardo del Crecimiento Fetal/diagnóstico , Recién Nacido de Bajo Peso , Arterias Umbilicales/química , Adulto , Ácidos Grasos/análisis , Ácidos Grasos Esenciales/fisiología , Femenino , Humanos , Recién Nacido , Músculo Liso Vascular/química , Fosfatidilcolinas/aislamiento & purificación , Fosfatidiletanolaminas/aislamiento & purificación , EmbarazoRESUMEN
6-Keto-PGF1 alpha, PGF2 alpha and PGE2 production by homogenates of aorta was unaffected by age, sex or smoking habits. Homogenates of saphenous vein from women aged 51-60 years produced greater and smaller amounts of 6-keto- PGF1 alpha and PGF2 alpha, respectively, than from women aged 41-50 and 61-70 years. In the 41-50 and 61-70 age groups, the amounts of 6-keto-PGF1 alpha and PGF2 alpha produced by homogenates of saphenous vein were smaller and greater, respectively, in women than in men. Cigarette smoking had no effect on PG production by homogenates of female saphenous vein. 6-Keto-PGF1 alpha production by homogenates of male saphenous vein was 20% lower in smokers and ex-smokers than in non-smokers, although this reduction was statistically significant only for ex-smokers. The amounts of PGE2 and PGF2 alpha produced by homogenates of male saphenous vein were smaller in smokers and ex-smokers, respectively, than in non-smokers. In spite of these changes in PG production by homogenates of saphenous vein, the basal outputs of PGs, particularly of 6-keto-PGF1 alpha, from the saphenous vein were little affected by age, sex or smoking habits.
Asunto(s)
Envejecimiento/metabolismo , Aorta/metabolismo , Prostaglandinas/biosíntesis , Vena Safena/metabolismo , Fumar/metabolismo , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radioinmunoensayo , Factores SexualesRESUMEN
Prostaglandin (PG) I2 (measured as 6-keto-PGF1 alpha) was the major PG synthesized by homogenates of the aorta from male rats, followed by lesser quantities of PGF2 alpha and PGE2. The amounts of 6-keto-PGF1 alpha synthesized by homogenates of the vena cava, mesenteric artery and femoral artery were much less than synthesized by the aorta, and were similar to the amounts of PGF2 alpha and PGE2 synthesized. The amounts of 6-keto-PGF1 alpha synthesized by homogenates of the aorta were 30% lower in female rats than in male rats. The amounts of 6-keto-PGF1 alpha and PGF2 alpha synthesized by homogenates of the aorta from female rats were similar, but the amounts of PGE2 synthesized were lower. The amounts of 6-keto-PGF1 alpha synthesized by homogenates of the aorta and femoral artery of female rats were similar, but the amounts of 6-keto-PGF1 alpha synthesized by homogenates of the mesenteric artery and vena cava were lower and were similar to the amounts of PGF2 alpha and PGE2 synthesized. The amounts of 6-keto-PGF1 alpha synthesized by the vena cava were significantly lower (P less than 0.05) and the amounts of 6-keto-PGF1 alpha and PGF2 alpha synthesized by the femoral artery and aorta, respectively, were significantly higher (P less than 0.05) in female rats than in male rats. The total amount of 6-keto-PGF1 alpha, PGF2 alpha and PGE2 synthesized by the aortae of male and female rats did not differ, indicating that the higher output of 6-keto-PGF1 alpha from the aorta of male rats compared to female rats is not due to a higher concentration of PGH2 synthetase in the aortic tissue of male rats. However, the shift in the relative amounts of 6-keto-PGF1 alpha and PGF2 alpha synthesized by the aorta of female rats in favour of PGF2 alpha may be responsible for the lower output of 6-keto-PGF1 alpha from the aorta of female rats. Oestradiol and progesterone had no effect on the amounts of 6-keto-PGF1 alpha, PGF2 alpha and PGE2 synthesized by homogenates of the aorta and vena cava from intact and ovariectomized, female rats. However, ovariectomy increased the amounts of 6-keto-PGF1 alpha and PGE2 synthesized by the aorta and vena cava, respectively, an effect not reversed by oestradiol and progesterone treatment.
Asunto(s)
Vasos Sanguíneos/metabolismo , Prostaglandinas/biosíntesis , 6-Cetoprostaglandina F1 alfa/biosíntesis , Animales , Dinoprost , Dinoprostona , Estro , Femenino , Técnicas In Vitro , Masculino , Ovario/fisiología , Prostaglandinas E/biosíntesis , Prostaglandinas F/biosíntesis , Ratas , Ratas Endogámicas , Factores SexualesRESUMEN
Prostaglandin (PG) I2 (measured as 6-keto-PGF1 alpha) was the major PG synthesized by aortic homogenates from normotensive and hypertensive male rats, with lesser quantities of PGF2 alpha and PGE2. Homogenates of vena cava from the same rats synthesized PGI2 and PGE2 in similar quantities. PGF2 alpha synthesis by aortic homogenates was significantly higher in hypertensive than in normotensive male rats. A similar trend was seen in PGF2 alpha synthesis by homogenates of the vena cava. Separation of the aorta of normotensive and hypertensive, male rats showed that PGI2 was the major PG synthesized by endothelial cells and smooth muscle, and that PGF2 alpha was the major PG synthesized by adventitia. PGI2 synthesis by smooth muscle and PGE2 synthesis by endothelial cells were lower, and PGF2 alpha synthesis by endothelial cells and smooth muscle were higher in hypertensive than in normotensive, male rats. PGI2 was the major PG released from the aorta of normotensive and hypertensive male rats, together with lesser quantities of PGE2 and PGF2 alpha. Aortic PGF2 alpha output, but not PGI2 and PGE2 outputs, was significantly higher in hypertensive compared to normotensive, male rats.
Asunto(s)
Vasos Sanguíneos/metabolismo , Epoprostenol/biosíntesis , Hipertensión/metabolismo , Prostaglandinas E/biosíntesis , Prostaglandinas F/biosíntesis , 6-Cetoprostaglandina F1 alfa/biosíntesis , Animales , Aorta/citología , Aorta/metabolismo , Dinoprost , Dinoprostona , Femenino , Masculino , Arterias Mesentéricas/metabolismo , Norepinefrina/farmacología , Ratas , Ratas Endogámicas , Valores de Referencia , Venas Cavas/metabolismoRESUMEN
The incidence of vascular disorders increases with age, and is also higher in men than in women. Since prostaglandin (PG)I2 produced by blood vessels has been proposed to have a protective function in the cardiovascular system, reduced vascular PGI2 production with age and lower vascular PGI2 production in males than in females may be causes for these increases in the incidence of vascular disorders. The production of prostaglandins by blood vessels has therefore been investigated in young (2 to 3 months) and old (12 to 14 months), male and female rats. The amounts of 6-keto-PGF1 alpha (reflecting PGI2 formation) synthesized by endothelial cell suspensions were significantly lower in old compared to young male rats, but did not differ between old and young female rats. The amounts of 6-keto-PGF1 alpha synthesized by homogenates of aortic smooth muscle were considerably higher in old compared to young, male and female rats. However, the basal output of 6-keto-PGF1 alpha from the perfused aorta in vitro did not change significantly with increase in age and, if anything, tended to be higher in the older rats, of both sexes. Furthermore, the basal output of 6-keto-PGF1 alpha from the aorta was significantly higher in young and old, male rats compared to young and old, female rats, respectively. Similar findings were observed regarding basal 6-keto-PGF1 alpha output from the perfused mesenteric arterial bed in vitro. The increases in output of 6-keto-PGF1 alpha from the mesenteric arterial bed in response to noradrenaline and angiotensin II were not diminished with age in either male or female rats. Consequently, PGI2 output from the blood vessels studied did not decrease with age, nor was it lower in male rats compared to female rats. The blood pressure was significantly higher in the old rats compared to the young rats. Also, the vascular output of PGF2 alpha, a vasoconstrictor, was higher in the old rats. The increase in blood pressure with age may therefore be connected with this increase in vascular PGF2 alpha production in both sexes.