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Biomedical subjects

J L Gordon

Publications and source records attributed to J L Gordon.

At least 109 records · Page 6Linked to original sources
PubMed1975

Specific binding sites for 5-hydroxytryptamine on rat blood platelets.

5-Hydroxytryptamine changes the shape of rat blood platelets by combination with a cinanserin-sensitive receptor which is not associated with the active uptake of 5-hydroxytryptamine. Binding of 5-hydroxy[3H]tryptamine to platelets at 4 degrees C demonstrates the presence of three saturable sites, and the highest-affinity site is apparently this 5-hydroxytryptamine receptor.

Animals↗
PubMed1975

Platelet function in C6-deficient rabbits. Aggregation and secretion induced by collagen and zymosan.

Platelet aggregation and the selective release of 5-hydroxytryptamine (5HT) and adenine nucleotides were measured in platelet-rich plasma (PRP) and washed platelet suspensions from control and C6-deficient rabbits. Aggregation and release induced by collagen were similar in both groups of animals. Aggregation responses to zymosan in control PRP samples were biphasic, and only the second phase was associated with release. In C6-deficient PRP samples, zymosan-induced aggregation lacked the second phase and there was no release of 5HT or adenine nucleotides. Zymosan induced no aggregation in washed platelet suspensions unless cell-free plasma was also added. C6-deficient plasma supported only primary aggregation, but the addition of control plasma resulted in biphasic aggregation and release. Zymosan which had been pre-activated in control or C6-deficient cell-free plasma induced primary aggregation in washed platelet suspensions. To obtain secondary aggregation and release, the addition of control plasma to the platelet suspension was necessary.

Adenine Nucleotides↗
PubMed1974

A simple fluorimetric microassay for adenine compounds in platelets and plasma and its application to studies on the platelet release reaction.

1. The formation of a stable fluorescent product between chloroacetaldehyde and adenine or its derivatives provides the basis of a rapid simple assay for total adenine compounds in blood platelets and in plasma. The assay will measure down to 200pmol of adenine nucleotides. An evaluation of the method established the optimum conditions for the production of maximum fluorescence. 2. Values obtained for total adenine compounds in platelets were 12.9nmol/10(8) cells in man and 7.8nmol/10(8) cells in rat. These closely agree with previous values for total platelet adenine nucleotides found by using a firefly luciferase assay, or a recycled NAD-linked photometric assay. This supports the concept that the chloroacetaldehyde reaction measures total adenine nucleotides in platelets. 3. Platelet aggregation induced by collagen was studied photometrically in 0.1ml volumes of citrated platelet-rich plasma, and total adenine nucleotides were assayed in platelets and plasma before and after aggregation. During aggregation 58% of adenine nucleotides were released from human platelets, and 36% from rat platelets. 4. The chloroacetaldehyde assay is no substitute for more sophisticated procedures, but is a simple sensitive means of monitoring the release of adenine nucleotides from blood platelets and is particularly valuable when small plasma samples must be used.

Acetaldehyde↗