RESUMEN
In vitro lipolysis by adrenaline, adrenaline + phentolamine (alpha-blocker) and isoprenalin (beta-agonist) was studied in deltoid and trochanter adipose tissues of sixteen obese females (10 android and 6 gynoid). Lipolysis differs in the upper and lower parts of the body. The more the obesity predominates in the upper part of the body, the more this difference is significant. If the actions of adrenaline in gynoid obese women are identical in deltoid and trochanter adipose tissues, the alpha-antilipolytic effect is more powerful than the beta-antilipolytic effect on the trochanter adipose tissue of android obese women.
Asunto(s)
Tejido Adiposo/metabolismo , Epinefrina/farmacología , Lipólisis/efectos de los fármacos , Adulto , Anciano , Antropometría , Femenino , Humanos , Isoproterenol/farmacología , Persona de Mediana Edad , Obesidad/metabolismo , Fentolamina/farmacologíaAsunto(s)
Pollos/sangre , Patos/sangre , Proteínas de Unión a Tiroxina/metabolismo , Animales , MasculinoRESUMEN
The reversible binding of 3,5-diiodotyrosine (DIT) to human and bovine serum protein and to purified human serum prealbumin and human and bovine albumin has been studied by equilibrium dialysis. Maximum binding occurred at pH 8.6-9.0. Human serum bound DIT less than did bovine serum. Adult ox and fetal calf sera showed similar binding. The main DIT-binding protein of human serum was prealbumin. It showed a single affinity site with a Ka of 0.85 X 10(6) M-1 at pH 8.6 and 0.40 X 10(6) M-1 at pH 7.4. The affinity constant of serum albumin for DIT was 2.8 X 10(3) M-1 at pH 8.6. The elevated binding of DIT to bovine serum is essentially due to albumin whose affinity constant for DIT is 16-times higher than that of human serum albumin. Fetuin was not responsible for any noticeable DIT binding in fetal calf serum.
