Search PubMed⌕ Search

Biomedical subjects

G B West

Publications and source records attributed to G B West.

At least 73 records · Page 4Linked to original sources
PubMed1978

Inhibitors of gastric lesions in the rat.

The production by stress of gastric lesions in rats was inhibited by metiamide and by mepyramine. Lesions induced by indomethacin treatment were inhibited by mepyramine but not by metiamide. Those induced by aspirin treatment in pylorus-ligated rats were not affected by either antihistamine drug. Oral glutamine inhibited lesion production in all three systems whereas aspirin orally markedly potentiated it. Sodium salicylate inhibited both indomethacin-induced lesions and those produced by aspirin in pylorus-ligated rats. On the other hand, copper salicylate inhibited stress-induced lesions and it, like copper aspirinate, also markedly reduced the extent of lesions produced by aspirin. On the basis of these results, stress-induced lesion production offers a suitable animal model for testing anti-ulcer drugs as it is, like most human gastric ulcers, inhibited by H2-receptor inhibitors like metiamide.

Animals↗
PubMed1978

Further studies on the structural requirements of sugars as antagonists of the changes in vascular permeability produced by sugar polymers in rat skin.

Hexoses and pentoses, but not tetroses or trioses, are potent inhibitors of the increase in vascular permeability in rat skin produced by the polysaccharides--dextran, mannan and glucan. The most active sugars are those with a D-threo type of structure in their cyclic form. The alcohols corresponding to the active sugars are much less inhibitory in this test. The results provide further information on the possible role of carbohydrate structures in antibody binding.

Animals↗
PubMed1978

Insulin and the dextran reaction in the rat.

Insulin potentiated the dextran anaphylactoid reaction in untreated rats and in rats pretreated with a protein synthesis inhibitor or with a lymphopenic agent. Incubation of rat lymphatic tissue with insulin failed to produce a factor potentiating the histamine-releasing action of dextran when this was studied in both in vivo and in vitro tests. It thus seems that insulin is exerting its potentiating effect on the dextran response through processes not involving synthesis of new protein or interaction with lymphocytes.

Anaphylaxis↗
PubMed1978

Glucans and dextrans in rats and man.

Intracutaneous injections of three glucan contaminants of invert sugar solutions and crude cane sugar into human skin produced localised wheals and erythema reactions. These glucans of molecular weight between 12,000 and 1,400,000 were also active on intradermal injection into both dextran-sensitive and dextran-resistant rats, and, like dextrans, were active on subcutaneous injection into dextran-sensitive animals.

Animals↗
PubMed1977

The insulin-like action of Bordetella pertussis vaccine in rats.

Treatment of rats with Bordetella pertussis vaccine significantly lowered the blood sugar level 4 days later but the vaccine did not alter the level in diabetic rats. The vaccine, like insulin, raised glycogen levels in liver, skeletal muscle and heart and reduced the plasma free fatty acid concentration. The action of a beta-adrenoceptor blocker was potentiated by the vaccine but not by insulin. Part of the hypoglycaemic action of the vaccine is probably due to beta-adrenoceptor blockade.

Adrenergic beta-Antagonists↗
PubMed1977

Anaphylactoid responses in rats.

The relative activities of dextran, mannan and ovomucoid as agents inducing anaphylactoid responses in rats vary with the route of injection, mannan being the most active especially by the intradermal route. All of these responses are potentiated by pretreatment with insulin and inhibited by glucose. Carrageenan and concanavalin A are also active but only by the subcutaneous route. Whereas the concanavalin A response is potentiated by insulin, that of carrageenan is reduced. There are therefore at least three classes of agents capable of inducing anaphylactoid responses in rats.

Anaphylaxis↗
PubMed1977

Involvement of the kinin system in the insulin-induced inhibition of carrageenin oedema in rats.

The carrageenin-induced foot oedema in rats is considerably decreased by insulin pretreatment, but increased in alloxan diabetes. Maximum inhibition by insulin occurs in the early phase of the oedema reaction and the insulin action is even further increased when it is administered 30 min after carrageenin. Doses of insulin as low as 1 U/kg intravenously produce significant inhibition. Determinations of the components of the kinin system indicate that the kininogenase activity is increased, and both the kininogen and kininase content are in turn decreased in the plasma of insulin-treated animals. When the carrageenin-induced oedema fluid of the paw after insulin is analysed for kininogen and kininase, their levels are significantly decreased when compared with those of oedema fluid without insulin. Histamine content in the oedema fluid is significantly enhanced by insulin. The anti-inflammatory effect of insulin under these conditions therefore appears to involve changes in the kinin system.

Animals↗
PubMed1976

The interaction between anthelmintic drugs and histamine in Ascaris suum.

1 Piperazine reduced the histamine content of Ascaris suum, yet it greatly increased the uptake of histamine from the surrounding medium, the neuromuscular structures of the nematode preferentially increasing in amount. 2 Bephenium reduced the histamine content of Ascaris and the uptake of histamine from the surrounding medium. However, the relative amount in the neuromuscular structures increased. 3 The flaccid paralysing action of piperazine may thus involve increased histamine absorption whereas the spastic paralysing action of bephenium may be independent of histamine.

Amine Oxidase (Copper-Containing)↗
PubMed1976

Immunosuppressive activity of concanavalin A.

Daily intraperitoneal doses of concanavalin A (Con A) produced a dose-related inhibition of adjuvant-induced arthritis in rats. Con A was also effective on established arthritis, markedly relieving the disease after only three doses. The inhibitory effect of Con A was neutralised by pre-incubation with ovalbumin, although this treatment did not modify the delayed phlogistic action of Con A in rat paws.

Animals↗
PubMed1976

A comparison of the anaphylactoid actions of a synthetic linear dextran and a natural branched dextran.

Synthetic linear dextran of molecular weight 40,000 produces the systemic anaphylactoid reaction in rats although it is about 4 times less active than the natural branched dextran of similar molecular weight. Similarly, it is less active on local injection into the foot or skin. However, in rats which have been bred for non-reactivity to systemic dextran, it is more active on local injection, resembling the activity of a branched natural dextran of much lower molecular weight (6,000). In human skin, the synthetic linear 40,000 sample is also more active than the natural branched sample of similar molecular weight in producing a wheal and erythema. The results suggest that the dextran receptor in the skin of man may be similar to that in rats genetically resistant to systemic dextran.

Anaphylaxis↗
PubMed1976

Anaphylactoid responses of two types of genetically different rats to horse serum and yeast.

Rats selectively bred for non-reactivity to clinical dextran (NR rats) fail to exhibit the anaphylactoid reaction to systemic baker's yeast or horse serum. Rats which respond with an anaphylactoid reaction to clinical dextran (R rats) react to baker's yeast but do not react to horse serum. The widespread oedema produced in R rats by systemic baker's yeast provides yet another clear method of differentiating them from NR rats.

Anaphylaxis↗
PubMed1976

Sugar polymers in rats and man.

Intracutaneous injections of a glucan contaminant of invert sugar solutions and crude cane sugar into human skin produced a localised wheal and erythema reaction. The glucan was also active on intradermal injection into both dextran-sensitive and dextran-resistant rats.

Animals↗
PubMed1976

Anaphylactoid reactions in rats and the blood sugar level.

When the blood sugar level in rats is reduced by insulin, the carrageenan-anaphylactoid reaction in one hindpaw is inhibited although the dextran-anaphylactoid reaction in the other hindpaw of the same animals is potentiated. When the blood sugar level is raised after alloxan pretreatment, the carrageenan reaction is potentiated whereas the dextran reaction is inhibited. The results support the hypothesis that the two local irritants exert their effects by involving different mechanisms.

Alloxan↗
PubMed1976

Carrageenan and dextran in rats.

Carrageenan injected subcutaneously into one hindpaw of the rat produces an anaphylactoid reaction which prevents the same paw responding to a second dose 14 days later but does not alter the response to dextran. However, dextran does not modify the response of the hindpaw to a subsequent dose of either dextran or carrageenan 14 days later. When using these models of inflammation for testing the anti-inflammatory activity of drugs, valuable extra information may be gained by adopting the cross-over technique and using both paws of each animal.

Anaphylaxis↗