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Role of phospholipids in adenylate cyclase and Na+-K+ ATPase activities or rat heart sarcolemma
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P. Niqam, S. Kirti, S. Saxena and K.C. MYOCARDITIS IN HEPATIC AMOEBIASIS. M.L.B. Medical College, Jhansi-284001, India. Samuel. Twenty cases of myocarditis (13 amoebic liver abscess and 7 amoebic hepatitis) were detected among 290 cases of hepatic amoebiases during the last 8 years with the incidence of 6.9 per cent. It is commonly seen in young adults (below 40 years). There was unaccountable dyspnoea with easy fatiquability (18 cases), palpitation (15 cases) and pain in chest (10 cases). Tachycardia was out of proportionate with muffled first heart sound and ejection systolic murmur over left sternal border (18 cases). Various electrocardiographic changes pertaining to myocarditis were; - cardiac arrhythmias (paroxysmal nodal tachycardia = 2 and sinus bradycardia = 3 cases), T inversion (4 cases), ST-segment depressRV5 + SV2 more than 45 mm (8 cases), prolong PR interval ion (5 cases), (1 cases) and lengthening of QT interval (3 cases,). High serum transaminases levels were related to hepatic as well as myocardial involvement. which could be performed in 7 cases, revealed presence Cardiac biopsy, of inflarnnatory cells with giant cells (5 cases) and associated necrosis Thus it can be concluded that myocarditis of muscle fibres (3 cases). in these of hepatic amoebiasis were due to amoebae.
ROLE OF PHOSPHOLIPIDS IN ADENYLATE CYCLASE AND Na+-K+ ATPase ACTIVITIES OF PAT HEART SARCOLEMMA. M.S. Nijjar, K.S. Dhalla and N.S. Dhalla, Departments of Pathology and Physiology, University of Manitoba, Winnipeg, Canada R3E OW3. It is generally held that phospholipids play a crucial role in the function of membrane bound enzymes: however, such an information with respect to heart sarcolemma is not available in the literature. In this study therefore we have examined changes in the adenylate cyclase and Na+-K+ ATPase activities as well as phospholipid composition of sarcolemma after treatments with different phospholipases. Rat heart sarcolemma was isolated by hypotonic shock-LiBr treatment method and incubated in the absence or presence of phospholipases A, C or D (250 - 500 uq/mq protein) for 10 min at 30°C. Treatment with phospholipase A was found to decrease phosphatidylcholine and phosphatidylethenolamine whereas lysophosphatidylcholine, phosphatylserine and phosphatidylinositol were increased markedly. Both adenylate cyclase and Na+ - K' ATPase activities decreased by treatment of sarcolemma with phospholipase A. Different pattern of changes in phospholipid composition was observed upon treatments with phospholipase C or D and varying degrees of changes in the sarcolemmal adenylate cyclase and Na+ - K+ ATPase activities were noted. These results suggest a complex role of phospholipids in the heart sarcolemmal bound enzyme activities. (Supported by the Medical Research Council of Canada).
P. Niqam, S. Kirti, S. Saxena and K.C. MYOCARDITIS IN HEPATIC AMOEBIASIS. M.L.B. Medical College, Jhansi-284001, India. Samuel. Twenty cases of myocarditis (13 amoebic liver abscess and 7 amoebic hepatitis) were detected among 290 cases of hepatic amoebiases during the last 8 years with the incidence of 6.9 per cent. It is commonly seen in young adults (below 40 years). There was unaccountable dyspnoea with easy fatiquability (18 cases), palpitation (15 cases) and pain in chest (10 cases). Tachycardia was out of proportionate with muffled first heart sound and ejection systolic murmur over left sternal border (18 cases). Various electrocardiographic changes pertaining to myocarditis were; - cardiac arrhythmias (paroxysmal nodal tachycardia = 2 and sinus bradycardia = 3 cases), T inversion (4 cases), ST-segment depressRV5 + SV2 more than 45 mm (8 cases), prolong PR interval ion (5 cases), (1 cases) and lengthening of QT interval (3 cases,). High serum transaminases levels were related to hepatic as well as myocardial involvement. which could be performed in 7 cases, revealed presence Cardiac biopsy, of inflarnnatory cells with giant cells (5 cases) and associated necrosis Thus it can be concluded that myocarditis of muscle fibres (3 cases). in these of hepatic amoebiasis were due to amoebae.
ROLE OF PHOSPHOLIPIDS IN ADENYLATE CYCLASE AND Na+-K+ ATPase ACTIVITIES OF PAT HEART SARCOLEMMA. M.S. Nijjar, K.S. Dhalla and N.S. Dhalla, Departments of Pathology and Physiology, University of Manitoba, Winnipeg, Canada R3E OW3. It is generally held that phospholipids play a crucial role in the function of membrane bound enzymes: however, such an information with respect to heart sarcolemma is not available in the literature. In this study therefore we have examined changes in the adenylate cyclase and Na+-K+ ATPase activities as well as phospholipid composition of sarcolemma after treatments with different phospholipases. Rat heart sarcolemma was isolated by hypotonic shock-LiBr treatment method and incubated in the absence or presence of phospholipases A, C or D (250 - 500 uq/mq protein) for 10 min at 30°C. Treatment with phospholipase A was found to decrease phosphatidylcholine and phosphatidylethenolamine whereas lysophosphatidylcholine, phosphatylserine and phosphatidylinositol were increased markedly. Both adenylate cyclase and Na+ - K' ATPase activities decreased by treatment of sarcolemma with phospholipase A. Different pattern of changes in phospholipid composition was observed upon treatments with phospholipase C or D and varying degrees of changes in the sarcolemmal adenylate cyclase and Na+ - K+ ATPase activities were noted. These results suggest a complex role of phospholipids in the heart sarcolemmal bound enzyme activities. (Supported by the Medical Research Council of Canada).