Drug Name Zanaflex

Thromboxane A2 and prostacyclin play a role in regulating the aggregability of platelets and vascular diameter (p. 150). Leukotrienes increase capillary permeability and serve as chemotactic factors for neutrophil granulocytes.
At 2 mg/kg, one out of 10 animals reacts; at 10 mg/kg, 5 out of 10 respond. The dose-frequency relationship results from the different sensitivity of individuals, which as a rule exhibits a log-normal distribution (C, graph at right, linear scale).

 

Zolpidem (an imidazopyridine) and zopiclone (a cyclopyrrolone) are hypnotics that, despite their different chemical structure, possess agonist activity at the benzodiazepine receptor (p. 226). Due to their narrower margin of safety (risk of misuse for suicide) and their potential to produce physical dependence, barbiturates are no longer or only rarely used as hypnotics.
Metabolically active vitamin D hormone results from two successive hydroxylations: in the liver at position 25 ( calcifediol) and in the kidney at position 1 ( calcitriol = vit. D hormone). 1-Hydroxylation depends on the level of calcium homeostasis and is stimulated by parathormone and a fall in plasma levels of Ca2+ or phosphate.