RESUMO
BACKGROUND: Karwinskia humboldtiana (Kh) is a poisonous plant of the rhamnacea family. To elucidate some of the subcellular effects of Kh toxicity, membrane fluidity and ATPase activities as hydrolytic and as proton-pumping activity were assessed in rat liver submitochondrial particles. Rats were randomly assigned into control non-treated group and groups that received 1,1.5 and 2 g/Kg body weight of dry powder of Kh fruit, respectively. Rats were euthanized at day 1 and 7 after treatment. RESULTS: Rats under Kh treatment at all dose levels tested, does not developed any neurologic symptoms. However, we detected alterations in membrane fluidity and ATPase activity. Lower dose of Kh on day 1 after treatment induced higher mitochondrial membrane fluidity than control group. This change was strongly correlated with increased ATPase activity and pH gradient driven by ATP hydrolysis. On the other hand, membrane fluidity was hardly affected on day 7 after treatment with Kh. Surprisingly, the pH gradient driven by ATPase activity was significantly higher than controls despite an diminution of the hydrolytic activity of ATPase. CONCLUSIONS: The changes in ATPase activity and pH gradient driven by ATPase activity suggest an adaptive condition whereby the fluidity of the membrane is altered.
Assuntos
Animais , Masculino , Ratos , Mitocôndrias Hepáticas/efeitos dos fármacos , Adenosina Trifosfatases/metabolismo , Karwinskia/toxicidade , Fluidez de Membrana/efeitos dos fármacos , Frações Subcelulares/efeitos dos fármacos , Partículas Submitocôndricas/efeitos dos fármacos , Mitocôndrias Hepáticas/enzimologia , Distribuição Aleatória , Ratos Sprague-Dawley , Força Próton-Motriz/efeitos dos fármacos , Frutas/toxicidadeRESUMO
Bullous pemphigoid has been reported in multiple publications to be associated with malignant neoplasms of different internal organ systems. This relationship was studied among forty patients seen at the Dermatology Clinics of the Puerto Rico Medical Center. The study demonstrated that Puerto Rican patients with bullous pemphigoid do not show an increased incidence of internal malignancy when compared with the general population matched for age, sex and study period. We conclude that extensive diagnostic studies for malignant neoplasms should not be the standard of care in patients with bullous pemphigoid. Additional studies should be guided by the clinical history and physical findings