Do insects really have a homeostatic hypotrehalosaemic hormone?

1. Biol Rev Camb Philos Soc. 1989 Nov;64(4):305-16.

Do insects really have a homeostatic hypotrehalosaemic hormone?

Veenstra JA.

Since trehalose in insects, in contrast to glucose in mammals, does not enter the
haemolymph directly from the digestive tract, but is all synthesized by the
insect itself, and furthermore an increased trehalose synthesis during stress and
flight does not lead to significant increases in haemolymph trehalose, there
seems to be no physiological need for an insect homeostatic hypotrehalosaemic
hormone. Experiments in which tissue extractions were found to lower haemolymph
trehalose can not prove the existence of such a hormone, while all insect species
which so far have been submitted to a trehalose-tolerance test, decrease their
haemolymph trehalose concentrations at a rate which can be accounted for by the
metabolic use of trehalose. These results therefore indicate the absence, and not
the presence, of a homeostatic hypotrehalosaemic hormone. This is also true for
blowflies, from which an insulin-like immunoreactive peptide has been isolated.
It seems therefore unlikely that this insulin-like peptide is a homeostatic
hypotrehalosaemic hormone. The physiological mechanism by which this insulin-like
peptide would have to act to function as a hypotrehalosaemic hormone is also an
unlikely one. It therefore seems justified to conclude that so far, homeostatic
hypotrehalosaemic hormones have not been demonstrated in insects. Furthermore, it
may well be that they do not exist.

DOI: 10.1111/j.1469-185x.1989.tb00678.x
PMID: 2696560 [Indexed for MEDLINE]

Know more about