Korean J Pediatr.  2004 Nov;47(11):1210-1215.

Possible Neuroprotective Role of Exogenous Growth Hormone on Hypoxic-Ischemic Brain Injury in Neonatal Rats

• Chang YP
• Jung MK
• Jee YH
• Cho JJ
• Lee SB
• Park WS
• Kim JW
• Shin DH

Abstract

PURPOSE
This study was performed to evaluate the possible neuroprotective effect of exogenous growth hormone on hypoxic-ischemic brain injury in neonatal rats.
METHODS
After ligation of the right common carotid artery, seven-day old Sprague-Dawley rats(n= 75) were exposed to 8% oxygen for two hours. In a growth hormone(GH)-treated group(n=25), each animal was subcutanously injected by GH(50 mg/kg, Grotrpin, Dong-Ah Pharmacy Co. KOREA) just before exposing to 8% oxygen, and then injected for the next two consecutive days by the same method. In a saline-treated group(n=25), the same amounts of saline were injected instead of GH. Other twenty five animals were sham-operated without hypoxia as a sham control group. The gross morphologic changes of extracted brains at three and seven days after injury were observed, and the ratios of wet and dry weight of each cerebral hemisphere ipsilateral and contralateral to hy poxic-ischemic injury were compared among three groups for evaluating the severity of brain edema. Also, the microscopic changes of cerebral cortex on coronal sections of paraffin-embedded brains were observed at three days after injury by light microscopy.
RESULTS
The GH injection reduced the severities of gross changes at seven days after HI injury. The brain edemas of ipsilateral cerebral hemispheres to the site of ligation of the right common carotid artery were significantly decreased in GH-treated animals at three days after HI injury, compared to those in saline-treated animals(P<0.05). On light microscopic examination, neurons with pyknosis of nucleus were remarkably reduced on cerebral cortex at three days after hypoxic-ischemic injury by GH treatment.
CONCLUSION
Exogenous GH might have a some neuroprotective role in hypoxic-ischemic brain injury of newborn rats.

Keyword

Growth hormone; Hypoxic-ischemic injury; Apoptosis; Brain; Newborn

MeSH Terms

Animals
Anoxia
Apoptosis
Brain Edema
Brain Injuries*
Brain*
Carotid Artery, Common
Cerebral Cortex
Cerebrum
Growth Hormone*
Humans
Infant, Newborn
Ligation
Microscopy
Neurons
Neuroprotective Agents
Oxygen
Pharmacy
Rats*
Rats, Sprague-Dawley
Growth Hormone
Neuroprotective Agents
Oxygen