The Canadian study, carried out on rats and published in science journal Experimental Physiology, designed to investigate why men suffer from sleep-disordered breathing more than women.
The findings suggest that a stressful experience in early life, such as separation from the mother, can disrupt the development of male babies’ hormone regulation systems.
One potential consequence of this disruption is respiratory problems in adulthood, including snoring.
In the study, carried out on male rats, those removed from their mothers in early life showed more breathing difficulties when the oxygen level was reduced, simulating the relaxation of the respiratory system which takes place during sleep, than those left undisturbed with their mothers.
Surgical ablation of the testes to lower testosterone levels in the body reduced these difficulties, supporting the results of previous studies carried out by the same team of scientists at the Centre de Recherche du CHU in Québec, which suggested that sex hormones can contribute to respiratory issues such as snoring.
When oxygen levels were lowered to simulate sleep in these studies, there was an increase in the levels of testosterone found in the blood of stressed rats. The studies suggested that this abnormal regulation of testosterone release contributed to the respiratory problems observed.
Dr Richard Kinkead, who led the study, said, ‘Over the past decade, our laboratory has established that neonatal stress has persistent and sex-specific effects on blood pressure and respiration, with consequences that persist well into adulthood.
‘We use rats because much like pre-term infants their brains are immature at birth and highly sensitive to stress. Moreover, there are similarities between their cardio-respiratory system and ours, so this study provides real insights into the conditions that cause respiratory disorders in the human population.’