MMQ

The MMQ cell line is a clonal, prolactin-secreting cell line derived from the 7315a rat pituitary tumor. It exclusively secretes prolactin and expresses functional dopamine receptors, specifically of the D2 subtype. Dopamine inhibits prolactin (PRL) release by reducing intracellular cyclic AMP (cAMP) levels and calcium uptake, as demonstrated in various experiments. This inhibition is reversed by haloperidol and pertussis toxin, confirming the role of GTP-binding proteins in dopamine's action. MMQ cells are also responsive to somatostatin (SRIF) and vasoactive intestinal polypeptide (VIP), but not to TRH, angiotensin II, or neurotensin.

MMQ cells proliferate rapidly, doubling in less than 24 hours under optimal conditions. When transplanted into rats, MMQ cells form tumors that increase serum prolactin levels without altering other hormones such as ACTH. This cell line is an important model for studying prolactin regulation, particularly in relation to dopamine and its inhibitory mechanisms on prolactin secretion.

37°C, 5% CO₂, humidified atmosphere.

1. Confirm that the vial remains deeply frozen upon delivery, as cells are shipped on dry ice to maintain optimal temperatures during transit.

2. Upon receipt, either store the cryovial immediately at temperatures below -150°C to ensure the preservation of cellular integrity, or proceed to step 3 if immediate culturing is required.

3. For immediate culturing, swiftly thaw the vial by immersing it in a 37°C water bath with clean water and an antimicrobial agent, agitating gently for 40-60 seconds until a small ice clump remains.

4. Perform all subsequent steps under sterile conditions in a flow hood, disinfecting the cryovial with 70% ethanol before opening.

5. Carefully open the disinfected vial and transfer the cell suspension into a 15 ml centrifuge tube containing 8 ml of room-temperature culture medium, mixing gently.

6. Centrifuge the mixture at 300 x g for 3 minutes to separate the cells and carefully discard the supernatant containing residual freezing medium.

7. Gently resuspend the cell pellet in 10 ml of fresh culture medium. For adherent cells, divide the suspension between two T25 culture flasks; for suspension cultures, transfer all the medium into one T25 flask to promote effective cell interaction and growth.

8. Adhere to established subculture protocols for continued growth and maintenance of the cell line, ensuring reliable experimental outcomes.

Mycoplasma contamination is excluded using both PCR-based assays and luminescence-based mycoplasma detection methods.

To ensure there is no bacterial, fungal, or yeast contamination, cell cultures are subjected to daily visual inspections.

For long-term preservation, place vials in vapor-phase liquid nitrogen at about −150 to −196 °C. Storage at −80 °C is acceptable only as a short interim step before transfer to liquid nitrogen.

Cryopreserved cell lines are shipped on dry ice in validated, insulated packaging with sufficient refrigerant to maintain approximately −78 °C throughout transit. On receipt, inspect the container immediately and transfer vials without delay to appropriate storage.

At Cytion, we stand behind the quality and viability of our products. We guarantee that our cells will be viable at the start of culture for 60 days after shipment from our facilities. We assure that all materials conform to the specifications described in the Certificate of Analysis and/or Product Sheet.

For full details, please refer to our Warranty Statement.