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And this research, led by Prof Allan Herbison, at the Otago University Centre for Neuroendocrinology, could help pave the way for further advances in infertility treatment.
The Otago-led researchers have just published the first direct evidence that it was kisspeptin neurons working in concert that generate the small, episodic hormone pulses that are crucial to normal reproductive functioning in humans and other mammals.
The findings were published this week in the prestigious journal Proceedings of the National Academy of Sciences (PNAS).
Prof Herbison, who is visiting the UK, said he was delighted New Zealand researchers continued to be ''at the forefront of fertility research''.
This was the third PNAS paper on fertility to come from the Centre for Neuroendrocrinology in the past 12 months.
''The work provides an important insight into how the brain controls fertility.
''We expect this to have future impact on regulating human fertility in the clinic,'' he said in an email interview.
Kisspeptins remained the ''most important discovery in understanding how the brain controls fertility''.
Researchers at the Otago centre continued to be ''at the very forefront of kisspeptin research and lead the world.''
Episodic pulses of gonadotropin-releasing hormone (GnRH) to the pituitary gland had long been known to be essential to maintain fertility, Prof Herbison said.
These episodic pulses - every hour or so - prompted the pituitary to release two key hormones (LH and FSH) into the bloodstream, also in a pulsing manner.
''Many types of infertility result from disorders of pulsatile hormone release, ranging from problems at puberty through to the inability to conceive.
''We are elucidating the mechanism that drives hormone pulses. These go too fast in some infertility conditions and too slow in others. So knowing how the brain generates these pulses will be ultimately be invaluable in treating infertility.''
It is thought up to one-third of all cases of infertility in women involve disorders in the area of brain circuitry Prof Herbison and his team study.
The research was supported by grants from the Health Research Council of New Zealand and the Royal Society's Marsden Fund.
• Kisspeptin was named after the Hershey Kiss chocolate by US researchers in Hershey, Pennsylvania.