Quinine (hydrochloride)

Quinine hydrochloride is an alkaloid extracted from cinchona bark and exhibits oral activity, acting as a potassium channel inhibitor. Quinine hydrochloride modulates the tolerance of red blood cells and presents dose-dependent toxicity and embryonic effects. Quinine hydrochloride is a typical hemolysin that directly lyses red blood cells, with cellular components of red blood cell membranes as its action targets. Quinine hydrochloride disrupts red blood cell membranes and induces hemolysis at high concentrations, while merely weakening the anti-hemolytic capacity of red blood cells at low concentrations. Quinine hydrochloride continuously reduces red blood cell tolerance after in vivo administration, and high doses can also alter blood cell counts. Quinine hydrochloride can be applied to researches related to red blood cell hemolysis, cancer and malaria^[1][2][3]. In Vitro:Quinine hydrochloride acts as a simple hemolysin on rabbit erythrocytes; pretreatment of rabbit erythrocytes reduces their resistance to the lytic effects of saponin and sodium taurocholate in vitro^[1]. In Vivo:Quinine hydrochloride (25-250 mg/kg per day; oral administration; daily dosing for 4 consecutive weeks) reduces food intake and body weight in rats, alters spleen weight in male rats, and decreases kidney and adrenal gland weights in female rats^[3].
Quinine hydrochloride (administered orally daily at doses of 1-200 mg/kg for 13 consecutive weeks) causes dose-dependent decreases in body weight and food intake, as well as reversible biochemical changes^[3].
Quinine hydrochloride (60-120 mg/kg per day; p.o.; daily administration; for 13 consecutive weeks) causes reversible inhibition of body weight gain, reduced food intake, and transient increases in kidney weight in male rats at doses ≥85 mg/kg per day^[3].
Quinine hydrochloride (85-200 mg/kg per day; p.o.; daily administration; for 13 consecutive weeks) does not induce ototoxic effects or hearing impairment^[3].
Quinine hydrochloride (50-200 mg/kg per day; p.o.; daily administration; gestational days 6-15) is orally administered to mated Sprague-Dawley rats on gestational days 6-15. Maternal toxicity occurs at doses ≥100 mg/kg, while mild fetal effects (decreased body weight, increased incidence of malformations) are observed at a dose of 200 mg/kg^[3].