Patterns of adrenoceptor change during liver regeneration of the wistar kyoto rat: A bunding study

Background. Adrenoceptors have been involved in the regulation of hepatocyte proliferation after partial hepatectomy, as well as in primary culture. This report characterized Ó1 and ß-adrenoceptor change during the time-course of liver regeneration in adult Wistar Kyoto rats. Methods. Saturation binding assays with [3H]prazosin or [3H]dihydroalprenolol (for Ó1- and ß-adrenoceptors, respectively) were done in liver plasma membranes from 6-monthold rats subjected to 70 percent hepatectomy followed by hepatic regeneration. Results. [3H]Prazosin and [3H]dihydroalprenolol binding gave control Bmax values of 101 ñ 10 and 12 ñ 1 fmol/mg protein and Kd of 0.50 ñ 0.10 and 4.1 ñ 0.4 nM for Ó1- and ß-adrenoceptors, respectively. Ó1-Adrenoceptor number and Kd increades at 24 and 48 h and returned to control values at 72 and 96 h after surgery, whereas ß-adrenoceptors augmented at 48 and 72 h, with a Kd change at 24 and 48 h postherapetectomy. Conclusions.These results suggest that dual control of Ó1- and ß-adrenoceptor membrane expression could be involved in different steps during hepatocyte proliferation, and that Wistar Kyoto rats have a different adrenoceptor pattern expression from other rat strains

Tratamento da hipertensäo arterial: monoterapia da hipertensäo leve a moderada com dose única diária de prazosina cápsulas de liberaçäo gradual (SR) / Treatment of essential hypertension: monoterapy of mild and moderate forms with single daily doses of sustained-release prazosin

A eficácia e a tolerabilidade de uma nova formulaçäo de liberaçäo gradual do bloqueador do receptor pós-dináptico alfa, prazosina, foram investigadas em um estudo clínico multicêntrico aberto de pacientes ambulatoriais portadores de hipertensäo essencial leve e moderada. Com a posologia de dose única diária, as pressöes arteriais sistólica e diastólica foram significativamente reduzidas logo ao início do tratamento e durante as 12 semanas da duraçäo do estudo. Em média, a freqüência cardíaca permaneceu constante inicialmente e durante os três meses do período de tratamento. A dose inicial de prazosina de liberaçäo gradual (1mg) proporcionou uma reduçäo suave e regular da pressäo arterial, com mínimos efeito colaaterais. Além disso, a eficácia da droga permaneceu inalterada após os três meses de tratamento