i am investigating neural and hormonal involvement in the action of the large intestine
do bacteria contribute any hormonal influence
Yes, bacteria do influence hormones and vice-versa, they cause changes in the pH and the environment thereby leading to influence on endocrine as well as non-endocrinological factors.
see a quote about it:-http://www.fhcrc.org/about/pubs/center_news/2005/oct20/sart2.html
"Some scientists have suspected that intestinal bacteria influence bone density because these bacteria metabolize sex hormones like estrogen, and sex hormones are known to influence bone growth and function. Different people have different types of bacteria living in the gut, which means that their bodies may metabolize sex hormones differently and thus have different effects on bone density."
When you talk about action of the large intestine influenced by hormones what exactly do you mean? Are you thinking along the lines of bacteria actually causing the secretion of hormones that induce the action?
One thing I do know is gut bacteria can react to secreted human hormones. For example, bacteria "communicate" with one another via quorum sensing. Essentially bacterial hormones and receptors. It is known that the human hormone epinephrine can interact with bacterial QS pathways and influence bacterial growth patterns and even cause disease states.
For an example, read this paper. Bacteria–host communication: The language of hormones
thanks for the help healthstation