Werkgroep 2: Farmacologische beïnvloeding van de maagzuursecretie.
Gebruikte literatuur: Boeing et al. (2016) Antiulcer mechanisms of Vernonia condensata Baker: A
medicinal plant used in the treatment of gastritis and gastric ulcer. Journal of Ethnopharmacology
184:196–207 (hoewel niet nodig om het hele artikel erbij te hebben is het eventueel wel raad te
plegen via link op Blackboard).
De Braziliaanse onderzoekers Boeing et al. hebben onderzocht of
een ethanolextract van de bladeren van de plant Vernonia
condensata (zie de figuur hiernaast) werkzaam is tegen een
maagzweer (ulcus ventriculi). De onderzoekers hebben gebruik
gemaakt van drie verschillende proefdiermodellen voor
maagzweren, die hieronder worden beschreven.
Ethanol-induced ulcer
Rats were divided in groups of six animals each and pretreated with vehicle (Veh: water plus 1%
Tween 80, 1 ml/kg, p.o.), carbenoxolone (Cbn: 200 mg/kg p.o.) or ethanolic extract (3, 30 and
300mg/kg, p.o.) one hour before they received 1 ml of ethanol (0.5 ml/100g) in order to induce
gastric ulcer. After 1 hour of the ethanol administration the animals were euthanized, the stomachs
were removed and opened along the greater curvature, and then area of lesion (mm 2) was
measured.
Nonsteroidal anti-inflammatory drug (NSAID)-induced ulcer
Rats were divided in groups of six animals each and pretreated with vehicle (Veh: water plus 1%
Tween 80, 1ml/kg, p.o.), carbenoxolone (Cbn: 200 mg/kg p.o.) or ethanolic extract (30 or 300mg/kg,
p.o.). One hour after treatment, all the rats received indomethacin 80mg/kg (p.o.) in order to induce
gastric ulcer. Six hours later, the animals were euthanized, the stomachs were removed and opened
along the greater curvature, and the area of lesion (mm 2) was measured.
Chronic gastric lesions induced by 80% acetic acid
Rats were divided in groups of six animals each and anaesthetized (xylazine 10mg/kg and ketamine
5mg/kg i.p.). The stomach was exposed through a midline epigastric incision and 500 µL of 80%
acetic acid was applied to the serosal surface of the stomach for 1 minute. Thereafter the acetic acid
was removed and the area of contact was washed with sterile saline.The animals were deprived of
food for the next 24 hours with free access to water and 48hours after the ulcer induction, the
treatment was initiated with vehicle (Veh: water plus 1% Tween 80 1ml/kg, p.o.), omeprazole (Ome:
20mg/kg), and ethanolic extract (300mg/kg) twice a day for 7 days. After the treatment period, the
rats were euthanized, the stomachs were removed and the area of lesion (mm 2) was measured.
Opdracht 1
Bestudeer de drie verschillende proefdiermodellen kritisch en vraag je bij ieder aspect van de
behandeling af hoe en waarom de onderzoekers het hebben uitgevoerd zoals ze hebben
beschreven. Zoek de woorden en begrippen op die je niet begrijpt/kent.
Bespreking (interactief) van opdracht 1 door de docent.
Opdracht 2
Stel dat de onderzoekers voor hun experiment mannelijke ratten hebben gebruikt. Wat kun je
zeggen over de leeftijd van deze proefdieren tijdens het experiment?
Gebruikte literatuur: Boeing et al. (2016) Antiulcer mechanisms of Vernonia condensata Baker: A
medicinal plant used in the treatment of gastritis and gastric ulcer. Journal of Ethnopharmacology
184:196–207 (hoewel niet nodig om het hele artikel erbij te hebben is het eventueel wel raad te
plegen via link op Blackboard).
De Braziliaanse onderzoekers Boeing et al. hebben onderzocht of
een ethanolextract van de bladeren van de plant Vernonia
condensata (zie de figuur hiernaast) werkzaam is tegen een
maagzweer (ulcus ventriculi). De onderzoekers hebben gebruik
gemaakt van drie verschillende proefdiermodellen voor
maagzweren, die hieronder worden beschreven.
Ethanol-induced ulcer
Rats were divided in groups of six animals each and pretreated with vehicle (Veh: water plus 1%
Tween 80, 1 ml/kg, p.o.), carbenoxolone (Cbn: 200 mg/kg p.o.) or ethanolic extract (3, 30 and
300mg/kg, p.o.) one hour before they received 1 ml of ethanol (0.5 ml/100g) in order to induce
gastric ulcer. After 1 hour of the ethanol administration the animals were euthanized, the stomachs
were removed and opened along the greater curvature, and then area of lesion (mm 2) was
measured.
Nonsteroidal anti-inflammatory drug (NSAID)-induced ulcer
Rats were divided in groups of six animals each and pretreated with vehicle (Veh: water plus 1%
Tween 80, 1ml/kg, p.o.), carbenoxolone (Cbn: 200 mg/kg p.o.) or ethanolic extract (30 or 300mg/kg,
p.o.). One hour after treatment, all the rats received indomethacin 80mg/kg (p.o.) in order to induce
gastric ulcer. Six hours later, the animals were euthanized, the stomachs were removed and opened
along the greater curvature, and the area of lesion (mm 2) was measured.
Chronic gastric lesions induced by 80% acetic acid
Rats were divided in groups of six animals each and anaesthetized (xylazine 10mg/kg and ketamine
5mg/kg i.p.). The stomach was exposed through a midline epigastric incision and 500 µL of 80%
acetic acid was applied to the serosal surface of the stomach for 1 minute. Thereafter the acetic acid
was removed and the area of contact was washed with sterile saline.The animals were deprived of
food for the next 24 hours with free access to water and 48hours after the ulcer induction, the
treatment was initiated with vehicle (Veh: water plus 1% Tween 80 1ml/kg, p.o.), omeprazole (Ome:
20mg/kg), and ethanolic extract (300mg/kg) twice a day for 7 days. After the treatment period, the
rats were euthanized, the stomachs were removed and the area of lesion (mm 2) was measured.
Opdracht 1
Bestudeer de drie verschillende proefdiermodellen kritisch en vraag je bij ieder aspect van de
behandeling af hoe en waarom de onderzoekers het hebben uitgevoerd zoals ze hebben
beschreven. Zoek de woorden en begrippen op die je niet begrijpt/kent.
Bespreking (interactief) van opdracht 1 door de docent.
Opdracht 2
Stel dat de onderzoekers voor hun experiment mannelijke ratten hebben gebruikt. Wat kun je
zeggen over de leeftijd van deze proefdieren tijdens het experiment?
