Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
1.
Acta Physiol Scand ; 106(4): 473-9, 1979 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-91306

RESUMEN

Sprague Dawley rats were sensitized with 20 microgram or 100 mg egg albumin (using pertussis vaccine as adjuvant). Mast cells isolated from the former group of animals showed a higher degree of histamine release upon challenge in vitro with egg albumin than those from the latter group. Using the lower amount of antigen for immunization mast cells from Hooded Lister rats showed an even higher degree of histamine release induced by antigen. An increased antigen-induced histamine release was associated with an increased spontaneous and phosphatidylserine-induced histamine release. Histamine release induced by phosphatidylserine was found to be specific in so far as it was calcium dependent and theophylline-inhibited. The basal level of cyclic AMP in mast cells was significantly depressed by sensitization. There was a relationship between the cyclic AMP/cyclic GMP ratio and the degree of spontaneous, phosphatidylserine-induced and anaphylactic histamine release. The results suggest that sensitization induces an increased release of histamine not only to the specific antigenic stimulus but also to more unspecific stimuli. Concomitantly there is a fall in the cyclic AMP/cyclic GMP ratio. The relationship between these two phenomena is discussed.


Asunto(s)
AMP Cíclico/análisis , Nucleótidos de Guanina/análisis , Guanosina Monofosfato/análisis , Liberación de Histamina/efectos de los fármacos , Inmunización , Mastocitos/fisiología , Fosfatidilserinas/farmacología , Anafilaxia , Animales , Mastocitos/enzimología , Mastocitos/inmunología , Ratas
9.
Biochem J ; 118(5): 851-7, 1970 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-5476728

RESUMEN

1. A method is described for the extraction, purification and separation of acid-soluble phosphorus compounds from mammalian semen. [8-(14)C]ATP and [8-(14)C]AMP were used as internal recovery standards to measure the breakdown and loss of these nucleotides in the procedure. 2. Bull, ram, boar and stallion semen was separated into seminal plasma and spermatozoa and the two fractions were examined separately. The overall composition of the mixture of the phosphorus compounds extracted from the two fractions was similar for the four species. 3. Glycerylphosphorylcholine and glycerylphosphorylinositol were the two phosphorus compounds identified in extracts of seminal plasma. ATP, ADP, AMP, GTP, GDP, NAD, fructose 1,6-diphosphate and glucose 6-phosphate were identified in extracts prepared from spermatozoa.


Asunto(s)
Fósforo/análisis , Semen/análisis , Nucleótidos de Adenina/análisis , Adenosina Trifosfato/análisis , Animales , Isótopos de Carbono , Bovinos , Glicerilfosforilcolina/análisis , Nucleótidos de Guanina/análisis , Hexosafosfatos/análisis , Caballos , Concentración de Iones de Hidrógeno , Masculino , Fosfolípidos/análisis , Ovinos , Solubilidad , Espermatozoides/análisis , Porcinos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA