JP Jan 19 16

Responses of python gastrointestinal regulatory peptides to feeding; 2001

Notes:

Peptide compositions begin to change before the food begins digesting (6 & 12 hours)

"Within 6 h after feeding (the first postfeeding sample), pythons experienced significant (a priori planned pairwise mean comparisons, P < 0.002) increases in plasma concentrations of CCK (assayed using CCK-2 antibody), GIP, and glucagon" (13638).

Figure 1; Plasma concentrations of CCK, Glucagon, GIP, Neurotensin increase and peak before 3 days.

Enzymes to make the hormones and then they need receptors.

Figure 2; multiple antibodies used to determine concentrations of CCK, Glucagon, Motilin, PYY across proximal - distal GI.

Figure 3; Antibodies must be binding to something else, as Gastrin should be highly expressed in the stomach.

"... we suspect that pythons do have gastrin but that its amino acid sequence makes it immunologically distinct from mammalian gastrin" (13641).

Figure 5; Vo is a large molecule, Vt is small. Synthetic substances used to give a marker size; anything that comes out around it should be the snake version. CCK and GIP are larger than the human synthetics.

Adaptive regulation of digestive performance in the genus Python; 2006

Notes:

Figure 6; small intestinal mass is increasing. Due to hypertrophy - individual cells growing, not more replicating. (Cells killed at the same rate as new cells made).

Figure 7; "Note that after feeding there is a lack of change in muscularis/serosa layer thickness and enterocyte height, and the significant increase in thickness of the mucosal layer and enterocyte width and volume" (350).

The mechanism "involving the movement to and from the brush- border membrane of intracellular stores of membrane proteins, explains the compensatory restoration of lost function following the surgical removal of a portion of the small intestine, as the remnant intestine responds by increasing villus length (Fenyö et al., 1976; Hanson et al., 1977)" (352).

• if this is true, we can't see this in mRNA. Unless, transcription upregulated for the second wave of inter-cellular proteins.

The cells also get fatter from lipid droplets (from the meal). Getting inside the cells via endocytosis.