DISTURBANCES IN SECRETIN HORMONE Secretin

Secretin is a hormone produced by the small intestine that plays a key role in digestion. Disturbances in secretin levels can impact digestive processes. For instance, overproduction of secretin may lead to excessive bicarbonate secretion, causing alkaline diarrhea. On the other hand, deficiencies in secretin can result in impaired digestion and absorption of nutrients. Monitoring secretin levels is crucial for understanding and managing digestive disorders.

1. University of Chakwal, Pakistan

2. Topic: Disturbances in Secretin Hormone
Department of Zoology
Presented by: Mishaal Naseer
Roll no# UOC-BSZOL-F2020/002
BS Zoology
Session: 2020-2024
Subject: Endocrinology
Instructor Name: Dr. Syeda Nadia Ahmed

3. Introduction
Discovery
Functions
Disturbances

4. Introduction
▪Secretinisa27aminoacidpeptidehormone.
▪ItisformedbyScellsfoundinduodenum.
▪Inactiveformofsecretinis“Prosecretin”thatisactivated
bygastricacid.
▪Secretinstimulatespancreas;plasmamembraneof
pancreaticcentroacinarcellshavesecretinreceptors
(Henriksen&Muckadell,2000).

5. Discovery
In1902,E.H.Starlingdiscovered“Secretin”in
collaborationwithW.M.Bayliss.
Itwasthefirst“ChemicalMessenger”identified.
Thistypeofasubstanceisnowcalledahormone,aterm
coinedbyBaylissin1905(Henriksen&Muckadell,
2000).

6. Functions
Secretinhasthreemainfunctions:
❖Regulatepancreastosecretepancreaticjuices.
❖Regulatewaterbalanceincells.
❖RegulatepHinsmallintestinebyinfluencinggastricacid
andbiocarbonaterelease(Chuetal.,2006).

7. Disturbances in Secretin Hormone
•Increasedproductionof
pancreaticjuiceandbicarbonate
Overproduction
•Lessreleaseofpancreatic
enzymesandbile
•Impairdigestion
Underproduction
•Receptorandsecretininteraction
problems
•Digestiveissues
Receptor
Sensitivity
Issues

8. Causative
Factors
Pancreatic Disorders
Small Intestinal
Disorders
Autoimmune
Disorders
Genetic Mutations
Medications and
Treatments
Infections
Tumors

9. Digestive Disorders
Secretinitselfdoesnotdirectlycausediseases,butabnormalities
initsfunctioncanleadtocertaindigestivedisorders:
➢PepticUlceration
➢Cholestasis
➢Zollinger-EllisonSyndrome
➢ChronicPancreatitis(Digregorio&Sharma,2019).

10. Peptic Ulceration
Itissecretindeficiencydisease
causedbyH.pyloriinfection.
Pepticulcerisaholeorsorein
theliningofstomach,intestine,
oesophagus.
H.pyloriinfectionincreases
gastricsecretionandreducesS-
cellpopulation(Malfertheiner
etal.,2009).
Fig. 1.1: Peptic Ulceration
https://thegidocs.com/wp-
content/uploads/2022/12/img29-1.png

11. Cholestasis
Cholestasisisaliverdisease.Itis
duetoincreasedquantityof
secretinreceptors.
Increasedsecretinsecretionleadsto
increasedbileductcellgrowthand
eventuallyliverdamage.Flowof
bilefromliverisreducedor
blocked(Elferink,2003).
Fig. 1.2: Cholestatic Liver Damage
https://www.opioidtreatment.net/wp-
content/uploads/2018/02/liver-
damage.jpg

12. Zollinger-Ellison Syndrome
Gastrinomas,thetumorsgrowin
pancreasorintheupperpartofsmall
intestine.Thesetumorsproducelarge
amountofhormonegastrin.
Gastrinlevelisstimulatedbysecretin
whichstimulatestheGcellsdirectly
andatsametimeinhibitGcell
indirectlybystimulatingsomatostatin
secretion(Hungetal.,2003).
Fig. 1.3: Zollinger-Ellison Syndrome
https://th.bing.com/th/id/R.d423d913df
6fe7062ec811cf534a0205?rik=s4r8eIc

13. Chronic Pancreatitis
Itisainflammationofpancreas.
Prolongedinflammationleadsto
structuralchangesinpancreas.
Thisdisruptsthenormalresponse
tosecretin,influencingenzyme
releaseandimpairingdigestion
(Braganzaetal.,2011).
Fig. 1.4: Chronic Pancreatitis
https://pocketdrugguide.com/wp-
content/uploads/2018/11/chronic-
pancreatitis-1.jpg

14. Social Behavior
Secretindeficientmiceshowreducedhippocampal
functionandsocialbehaviorbecausesecretinactsasa
neurotransmitterinthebrain.
Secretinalsoincreaseoxytocinreleaseinthebrain,
increasedsocialbehaviorinrats(Nishijimaetal.,
2006).

15. Secretin Stimulation Test
Thistestisusedtodiagnosepancreasdisordersand
diseases.Itisameasurementoftheabilityofpancreasin
responsetosecretin.
Inthistest,patientreceivessecretinthroughnoseorthroat
viaatube.After1-2hours,bloodlevelsofpancreatic
secretionsareelevated.
Abnormallevelofpancreaticsecretionstellthatthereare
problemsinthepancreas(Madhavan,2020).

16. References
Chatzipanagiotou,O.,Schizas,D.,Vailas,M.,Tsoli,M.,Sakarellos,P.,Sotiropoulou,M.&
Felekouras,E.(2023).Allyouneedtoknowaboutgastrinomatoday|Gastrinomaand
Zollinger‐Ellisonsyndrome:Athoroughupdate
Madhavan,P.,Aftab,H.,&Tendler,B.(2020).SAT-121SecretinStimulationTestinaPatient
ReceivingProtonPUMPInhibitorTherapy-toDoorNottoDo?.JournaloftheEndocrine
Society,4(Supplement_1),SAT-121.JournalofNeuroendocrinology,35(4),e13267.