快猫短视频

CAESAREAN babies may be more susceptible to schizophrenia than children born
naturally, say Canadian researchers who studied the effects of the operation on
rats. The finding raises doubts about the increasing number of Caesarean
sections performed for convenience.

Patricia Boksa and Bassem El-Khodor of McGill University in Montreal gave
pregnant rats general anaesthetics and delivered their young by Caesarean
section. The operations were uncomplicated and the rat pups appeared normal at
birth. But they grew into adults with marked differences compared with controls
born naturally.

鈥淭o our surprise, we kept finding dopamine system differences,鈥� says Boksa.
When the Caesarean rats were given amphetamines, for instance, drugs that
activate the dopamine system in the brain, they became far more active than the
other group, the researchers told last week鈥檚 meeting. The Caesarean rats also
had a far worse response to repeated tail pinching, a standard test for stress
reactions.

The results hint that babies born by Caesarean may be more vulnerable to
schizophrenia, which is thought to involve an overactive dopamine system and has
a statistical link with birth complications. But no one knows why a Caesarean
birth might increase the risk of developing the illness. Boksa thinks the
absence of hormonal surges when a baby is born naturally may play a role,
because these may be important for brain development. Boksa says we need more
evidence about the operation鈥檚 effects. 鈥淚 would question the Caesarean section
of convenience,鈥� she says.

鈥淭here鈥檚 a lot of discussion about complications precipitating schizophrenia
in genetically vulnerable people,鈥� says Barbara Fish of the University of
California at Los Angeles, who studies the effects of difficult births. But she
cautions that it is difficult to draw conclusions from the studies when many
environmental factors are involved.