Beta 1 - beta 2 blocking activity of propranolol and metoprolol in the unanaesthetized genetically hypertensive and normotensive rat.

The beta-antagonistic activity of propranolol and metoprolol has been evaluated, in terms of inhibition of isoproterenol effects, "in vitro" (isolated right atria and tracheae) and "in vivo" in unanaesthetized normotensive and spontaneously hypertensive rats (SHR). Metoprolol resulted 13 - 6.4 - 14 times more cardioselective than propranolol in the three aforementioned experimental models, respectively.

Bronchodilator activity in vivo and in vitro of four 13,14-didehydro-PGE2 analogues.

The bronchodilator activity of four analogues of PGE2: 13,14-didehydro-PGE2 (I), 20-methyl-13,14-didehydro-PGE2 (II), 16 S-methyl-13,14-didehydro-PGE2 (III) and 16 R-methyl-13,14-didehydro-PGE2 (IV) was studied in vivo and in vitro. The potency of III and IV when administered by aerosol to conscious guinea pigs was four times that of PGE2 in protecting against histamine-induced convulsion; I and II were less active. Compound III administered by aerosol to anaesthetized guinea pigs was six times more potent than PGE2 in protecting against i.

PGE2:PGE-2:

The biological activities of 8,12-diiso-PGE2 (ent-11,15-epi-PGE2), PGE2 and PGF2alpha have been compared in a series of pharmacological preparations intended to differentiate between F and E type of activity. Similar to PGF2alpha but unlike PGE2, 8,12-diiso-PGE2 increased the tone of isolated smooth muscle preparations of guinea pig trachea, guinea pig colonic circular layer, rabbit Fallopian tubes. The stimulation effect of 8,12-diiso-PGE2 and PGF2alpha on visceral smooth muscle was also shown in vivo: the two drugs were in all instances able to increase the miogenic activity and tone of rabbit uterus in situ, while these were depressed by PGE2.