Regular erections may play an important role in making sure men have healthy sex lives, research suggests.
The study in mice provides insights that could one day lead to new treatments for erectile dysfunction in humans, experts suggest.
Researchers at Karolinska Institutet and Uppsala University in Sweden found that cells called fibroblasts have a previously unknown and very important role to play in regulating blood flow in the penis.
Eduardo Guimaraes, researcher at the Department of Cell and Molecular Biology at Karolinska Institutet and first author of the paper, said: “Fibroblasts are the most abundant cells in the penis of both mice and humans but they have been neglected in research.
“Now we can show, using a very precise method called optogenetics, that they have a very important role in regulating blood flow in the penis, which is what makes the penis erect.”
Men’s sexual health and wellbeing largely depend on the ability to attain penile erections.
However, ageing and health risk factors including diabetes and narrowing of the arteries can affect this.
According to the findings, fibroblasts bring about erection by taking up chemicals that lead to the widening of blood vessels in the penis.
How effective this process is depends on the number of fibroblasts.
The study, published in Science, found that the number of fibroblasts in the penis is affected by the frequency of erections – the more frequent, the more fibroblasts, and vice versa.
Christian Goritz, senior researcher at the Department of Cell and Molecular Biology at Karolinska Institutet, said: “It’s not so strange really. If you exert yourself a lot, your body adapts.
“If you run regularly, it will eventually become easier to breathe while running.”
He said that in terms of what conclusions can be drawn for humans from studies on mice, in this case there are significant similarities, adding: “The basic mechanisms of erection are very similar in all mammals regarding anatomy, cell structure and so on
“However, there is one difference between humans and most mammals – they have a bone in their penis.
“This means that effective blood flow regulation is probably even more important for human reproduction.”
The researchers also found that older mice had fewer fibroblasts in the penis, which was also reflected in lower blood flow.
The ability to get an erection also decreases with age in humans, which could be partly due to fewer fibroblasts in the penis, the experts suggest.