Thromb Haemost 1985; 53(01): 095-098
DOI: 10.1055/s-0038-1661244
Original Article
Schattauer GmbH Stuttgart

Maternal and Fetal Platelet Responses and Adrenoceptor Binding Characteristics

C R Jones
The University Department of Materia Medica, Stobhill General Hospital, Glasgow, UK
,
R McCabe
The University Department of Materia Medica, Stobhill General Hospital, Glasgow, UK
,
C A Hamilton
The University Department of Materia Medica, Stobhill General Hospital, Glasgow, UK
,
J L Reid
The University Department of Materia Medica, Stobhill General Hospital, Glasgow, UK
› Author Affiliations
Further Information

Publication History

Received 31 July 1984

Accepted 12 November 1984

Publication Date:
18 July 2018 (online)

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Summary

Paired blood samples were obtained from mothers (venous) and babies (cord venous blood) at the time of delivery by caesarean section under epidural anaesthetic. Fetal platelets failed to aggregate in response to adrenaline in vitro although adrenaline could potentiate the threshold response to adenosine diphosphate (1 μM). Fetal platelet responses to collagen and 8 Arg vasopressin did not differ significantly from maternal responses. Maternal and fetal platelets also showed similar inhibition of aggregation after activation of adenylate cyclase (PGE1 and parathormone), in contrast to the inhibition of adenylate cyclase by adrenaline.

Alpha2 adrenoceptors were investigated using [3H] yohimbine binding receptor number and were reduced modestly but significantly on fetal compared to maternal platelets. The failure of fetal platelet aggregation in response to adrenaline appears to be related to a failure of receptor coupling and may represent a delayed maturation of fetal platelet alpha receptors or a response- to increased circulating catecholamines during birth.