Expression and activity of the Ca(2+)-atpase enzyme in human neonatal erythrocytes.
The plasma membrane Ca(2+)-ATPase (PMCA) is one of the main regulators of Ca(2+) homeostasis. We studied the perinatal alteration of the abundance and the activity of PMCA molecules in human erythrocytes in pre-term and full-term neonates and children at the age of 1-4 years. The lower abundance of the 4b isoform was associated with lower enzyme activity in full-term neonates compared to children. Although the number of PMCA molecules was higher in pre-term neonates, their total PMCA activities were identical to those of full-term neonates. Our findings suggest that the abundance of PMCA molecules changes during the perinatal development. The same activity at higher enzyme molecule numbers might indicate a potential immaturity of the enzyme in the pre-term infant.
Kocsis
I
I
First Department of Paediatrics, Semmmelweis Medical University, Budapest, Hungary. kopist@gyer1.sote.hu
Vásárhelyi
B
B
Héninger
E
E
Vér
A
A
Tulassay
T
T
D000375:Aging; D015153:Blotting, Western; D000252:Calcium-Transporting ATPases / Q000097:blood*; D002147:Calmodulin / Q000494:pharmacology; D002675:Child, Preschool; D004910:Erythrocyte Membrane / Q000201:enzymology*; D005865:Gestational Age; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature / Q000097:blood*
D002147:Calmodulin; D000252:Calcium-Transporting ATPases