Actually, nifedipine is a calcium channel blocker and does not result in 
appreciable nitric oxide release.  (Circulation.1998; 97: 576-580 doi: 
10.1161/01.CIR.97.6.576), that's how nitroglycerine works. One calcium 
channel blocker (amlodipine, brand name Norvasc in the US) does produce 
some NO release.

Calcium channel blockers like nifedipine bind to inactive calcium 
channels (specifically voltage-gated L-type calcium channels)  and 
stabilize them in the 'off' or inactive conformation. Arterial walls are 
rich in smooth muscles with these particular calcium channels, so are 
most likely to be affected by these drugs. This relaxes the smooth 
muscles in the small arteries, lowering blood pressure and reducing 
vasospasm.

One thing that can help women with MTHFR polymorphisms that are less 
active is to ensure adequate intake of other methyl donors, particularly 
the amino acid methionine. Vitamin B12 and riboflavin may also help them 
compensate.

This is all an interesting subject!

Catherine Watson Genna BS, IBCLC  NYC  www.cwgenna.com

On 5/8/2014 1:38 AM, Jennifer Tow, IBCLC wrote:
> Mary,
> Nifedipine is a drug that drives the production of nitric oxide. Nitric oxide is a vasodilator. There can be numerous reasons she is not making sufficient nitric oxide, from phenotypic mutations in the methylation pathways to insufficient substrate (L-arginine) to mouth breathing (nose breathing allows for normal nitric oxide production while mouth breathing creates a deficit). The easiest way to support nitric oxide production is to provide the substrate. Instead of a drug, she can simply take L-arginine. 500mg 3 x per day. It usually works within hours. You can search pubmed. It is very well referenced for treating Reynauds. A nice side effect is increased milk production for women whose nitric oxide pathway is impaired since we need good blood supply to the breasts to make milk.
> Jennifer Tow, IBCLC, USA & France
> Intuitive Parenting Network, LLC
>
>
>
> Date:    Wed, 7 May 2014 14:01:55 -0400
> From:    "Mary Jozwiak BS, IBCLC, RLC" <[log in to unmask]>
> Subject: Re: Resistant TT
>
> Thank you, Jeannette, Thank you, Kerri,
>
> Saw this Mom this morning. I suspected Raynauds originally, but mom was having
> such a rough time, she didn't understand. With the shower causing so much pain,
> and today, after the baby unlatched (using a shield on one side, because she's
> so overwhelmed with the pain and the baby has no idea what to do with his tongue
> yet, and the shield was helping him hold it down)  I sat there and watched the
> blanching spread across the flat tip of her nipple. She was more coherent and
> said, yes, her fingers and toes get white and cold and get "hives" after coming
> in from the cold. It makes total sense. She;ll be using warmth on the nipples
> immediately after each feeding and gently allow it to cool to room temperature,
> so the capillaries and vessels don't overreact to the pressure. suction and
> temperature changes. I've seen this work before, so I hope it does for her. If
> not, she can talk to her MD about Nifidipene.
>
> She's dealing with so much, but she's such a trooper. She's really working hard
> and I'm her biggest cheerleader (next to her baby and her husband, of course)
> The upper lip flanging is SO much better now. The baby has it figured out.
>
> We're using finger/mouth exercises and mimicking exercises (as of now, he really
> tries to mimic sticking out his tongue when you do it, and he laughs and smiles,
> and opens his little mouth and coos.... and can't quite get control of his
> tongue yet.) I did a gentle very soft sell when I gave her a list of CSTs, but
> they may need to come to that solution when it makes more sense to them.
>
> She knows I'm on her side. We talked about "resting" the nipple (the right one
> is much worse) and that she would do that as a last chance. She did OK with the
> shield (but with the Raynaud's it is still blanching in response to ANY
> pressure, suction, heat cold etc.)
>
> Thank you to all who emailed me as well. I see a lot of TT and TLF but this is a
> complicated case. Mom knows she can text or call or email me and I'll get back
> to her asap.
>
> Warmly,
>
> Mary Jozwiak, IBCLC, RLC
> Board Certified Lactation Consultant, Post Partum Doula
> Birthwaysinc.
> Chicago, IL
>
>
>
>
>
>
>
>   
>
>               ***********************************************
>
> Archives: http://community.lsoft.com/archives/LACTNET.html
> To reach list owners: [log in to unmask]
> Mail all list management commands to: [log in to unmask]
> COMMANDS:
> 1. To temporarily stop your subscription write in the body of an email: set lactnet nomail
> 2. To start it again: set lactnet mail
> 3. To unsubscribe: unsubscribe lactnet
> 4. To get a comprehensive list of rules and directions: get lactnet welcome


             ***********************************************

Archives: http://community.lsoft.com/archives/LACTNET.html
To reach list owners: [log in to unmask]
Mail all list management commands to: [log in to unmask]
COMMANDS:
1. To temporarily stop your subscription write in the body of an email: set lactnet nomail
2. To start it again: set lactnet mail
3. To unsubscribe: unsubscribe lactnet
4. To get a comprehensive list of rules and directions: get lactnet welcome