A sigh of relief: peptide that controls sighs found

It is not only relief, but often sadness or exhaustion may also cause sighing - a long breath. And, of course, there are also sighs without any of these - a spontaneous sigh that helps to reinflate the alveoli of your lungs. So what is the most proximal cause of sighing?

The center in the brain that controls breathing (retrotrapezoid nucleus) sends signals to the respiratory rhythm generator in the brain (preBötzinger Complex). These signals consist of two peptides: neuromedin B and gastrin-releasing peptide. A shot of these peptides elicits sighing. Blocking either of these peptides reduces sighing and blocking both peptides eliminates it altogether.

Whether it is relief from tension, emotions, tiredness or any other distal causes, this is the peptide that ultimately sets off a sigh.

A report in the recent issue of  Nature - 8th February 2016 - looks into the peptidergic control circuit for sighing.

Are you a morning person or a night owl?

Sleep researchers have been identifying genes that determine whether you get up early and go to bed early or lead a hectic life late at night, finding it easier to sleep into the morning hours. The first clock gene found was per in drosophila a few decades ago. The gene influences the circadian rhythm. And then a few more followed, one by one. Now in a fell swoop, using genome wide association studies, of self reported morning persons, scientists have identified 15 loci that contribute to the habit of rising early in the morning.

Interestingly, getting up early and going to bed early does not necessarily make you healthy, wealthy and wise. Excess body weight, depression etc have also been implicated for the tendency to rise early. But these factors do not seem to figure in the genetic analysis. Yet.

Nature Communications has open access report. Take a look.

http://www.nature.com/ncomms/2016/160202/ncomms10448/full/ncomms10448.html